added more vocabulary terms. better handling of namespaces/prefixes.

fixes #74
fixes #358
fixes #359

from core epub vocabulary:
- added `endnote`/`endnotes` in addition to the deprecated `rearnote`/`rearnotes`

from dictionaries vocabulary:
- `antonym-group`
- `condensed-entry`
- `def`
- `dictentry`
- `etymology`
- `example`
- `gram-info`
- `idiom`
- `part-of-speech`
- `part-of-speech-group`
- `part-of-speech-list`
- `phonetic-transcription`
- `phrase-group`
- `phrase-list`
- `sense-group`
- `sense-list`
- `synonym-group`
- `tran`
- `tran-info`

from indexes vocabulary:
- `index-editor-note`
- `index-entry`
- `index-entry-list`
- `index-locator`
- `index-locator-list`
- `index-locator-range`
- `index-term`
- `index-term-categories`
- `index-term-category`
- `index-xref-preferred`

from magazine vocabulary:
- `prism:title`
- `prism:deck`
- `prism:subtitle`
- `prism:byline`
- `prism:contributors`
- `prism:caption`
- `prism:credit`
- `prism:box`
- `prism:advertisement`
- `prism:pullQuote`
- `msv:article-region`
- `msv:article-text`
- `msv:media`
- namespaces:
    - `msv: http://www.idpf.org/epub/vocab/structure/magazine/#`
    - `prism: http://www.prismstandard.org/specifications/3.0/PRISM_CV_Spec_3.0.htm#`

from EDUPUB:
- `biblioref`
- `credit`
- `feedback`
- `fill-in-the-blank-problem`
- `general-problem`
- `glossref`
- `label`
- `learning-objective`
- `learning-objectives`
- `learning-outcome`
- `learning-outcomes`
- `learning-resource`
- `learning-resources`
- `learning-standard`
- `learning-standards`
- `match-problem`
- `multiple-choice-problem`
- `ordinal`
- `pullquote`
- `question`
- `referrer`
- `true-false-problem`

Removed `nordic272a` as it is redundant and actually had a bug in it
preventing correct usage of annotations.

Various other changes.

src/main/resources/xml/schema/nordic-html5.rng

@@ -365,9 +365,12 @@
             <a:documentation>The HTML root element (&lt;html&gt;) represents the root of an HTML document. All other elements must be descendants of this element.</a:documentation>
             <!-- HTML content model: head body -->
             <!-- Strict content model: head body -->
-            <attribute name="epub:prefix">
-                <value>z3998: http://www.daisy.org/z3998/2012/vocab/structure/#</value>
-            </attribute>
+            <optional>
+                <attribute name="epub:prefix">
+                    <!-- content validated in schematron -->
+                    <text/>
+                </attribute>
+            </optional>
             <ref name="attlist.html"/>
             <ref name="htmlcontent"/> <!-- head, body -->
         </element>
@@ -3166,6 +3169,7 @@
                     <optional>
                         <choice>
                             <value>rearnotes</value>
+                            <value>endnotes</value>
                             <value>footnotes</value>
                         </choice>
                     </optional>
@@ -3633,6 +3637,7 @@
             <value>index-legend</value>
             <value>index-group</value>
             <value>glossary</value>
+            <value>dictionary</value>
             <value>bibliography</value>
             <!--<value>titlepage</value>-->
             <value>halftitlepage</value>
@@ -3655,6 +3660,7 @@
             <value>practices</value>
             <value>footnotes</value>
             <value>rearnotes</value>
+            <value>endnotes</value>
             <value>page-list</value>
             <value>z3998:section</value>
             <value>z3998:subsection</value>
@@ -3703,6 +3709,7 @@
                 <!--<value>frontmatter</value>-->
                 <value>fulltitle</value>
                 <!--<value>glossary</value>-->
+                <!--<value>dictionary</value>-->
                 <value>glossdef</value>
                 <value>glossterm</value>
                 <value>halftitle</value>
@@ -3731,7 +3738,9 @@
                 <!--<value>preface</value>-->
                 <!--<value>prologue</value>-->
                 <value>rearnote</value>
+                <value>endnote</value>
                 <!--<value>rearnotes</value>-->
+                <!--<value>endnotes</value>-->
                 <!--<value>sidebar</value>-->
                 <!--<value>subchapter</value>-->
                 <value>subtitle</value>
@@ -3946,6 +3955,80 @@
                 <!--<value>z3998:warning</value>-->
                 <value>z3998:weight</value>
                 <!--<value>z3998:word</value>-->
+
+                <!-- dictionaries vocabulary -->
+                <value>antonym-group</value>
+                <value>condensed-entry</value>
+                <value>def</value>
+                <value>dictentry</value>
+                <value>etymology</value>
+                <value>example</value>
+                <value>gram-info</value>
+                <value>idiom</value>
+                <value>part-of-speech</value>
+                <value>part-of-speech-group</value>
+                <value>part-of-speech-list</value>
+                <value>phonetic-transcription</value>
+                <value>phrase-group</value>
+                <value>phrase-list</value>
+                <value>sense-group</value>
+                <value>sense-list</value>
+                <value>synonym-group</value>
+                <value>tran</value>
+                <value>tran-info</value>
+
+                <!-- indexes vocabulary -->
+                <value>index-editor-note</value>
+                <value>index-entry</value>
+                <value>index-entry-list</value>
+                <value>index-locator</value>
+                <value>index-locator-list</value>
+                <value>index-locator-range</value>
+                <value>index-term</value>
+                <value>index-term-categories</value>
+                <value>index-term-category</value>
+                <value>index-xref-preferred</value>
+
+                <!-- magazine vocabulary -->
+                <!-- msv: http://www.idpf.org/epub/vocab/structure/magazine/# -->
+                <!-- prism: http://www.prismstandard.org/specifications/3.0/PRISM_CV_Spec_3.0.htm# -->
+                <value>prism:title</value>
+                <value>prism:deck</value>
+                <value>prism:subtitle</value>
+                <value>prism:byline</value>
+                <value>prism:contributors</value>
+                <value>prism:caption</value>
+                <value>prism:credit</value>
+                <value>prism:box</value>
+                <value>prism:advertisement</value>
+                <value>prism:pullQuote</value>
+                <value>msv:article-region</value>
+                <value>msv:article-text</value>
+                <value>msv:media</value>
+
+                <!-- educational vocabulary (EDUPUB) -->
+                <value>biblioref</value>
+                <value>credit</value>
+                <value>feedback</value>
+                <value>fill-in-the-blank-problem</value>
+                <value>general-problem</value>
+                <value>glossref</value>
+                <value>label</value>
+                <value>learning-objective</value>
+                <value>learning-objectives</value>
+                <value>learning-outcome</value>
+                <value>learning-outcomes</value>
+                <value>learning-resource</value>
+                <value>learning-resources</value>
+                <value>learning-standard</value>
+                <value>learning-standards</value>
+                <value>match-problem</value>
+                <value>multiple-choice-problem</value>
+                <value>ordinal</value>
+                <value>pullquote</value>
+                <value>question</value>
+                <value>referrer</value>
+                <value>true-false-problem</value>
             </choice>
         </zeroOrMore>
     </define>