Refactor Enketo service code to allow for reuse by test harness

Gruntfile.js

@@ -305,7 +305,6 @@ module.exports = function(grunt) {
             'webapp/src/ts/**/*.component.html',
           ];
           const ignore = [
-            'webapp/src/ts/providers/xpath-element-path.provider.ts',
             'webapp/src/js/bootstrap-tour-standalone.js',
             'api/extracted-resources/**/*',
             'api/build/**/*',
@@ -540,11 +539,12 @@ module.exports = function(grunt) {
             'patch webapp/node_modules/moment/locale/hi.js < webapp/patches/moment-hindi-use-euro-numerals.patch',
 
             // patch enketo to always mark the /inputs group as relevant
-            'patch webapp/node_modules/enketo-core/src/js/Form.js < webapp/patches/enketo-inputs-always-relevant.patch',
+            'patch webapp/node_modules/enketo-core/src/js/form.js < webapp/patches/enketo-inputs-always-relevant_form.patch',
+            'patch webapp/node_modules/enketo-core/src/js/relevant.js < webapp/patches/enketo-inputs-always-relevant_relevant.patch',
 
-            // patch enketo so forms with no active pages are considered valid
-            // https://github.com/medic/medic/issues/5484
-            'patch webapp/node_modules/enketo-core/src/js/page.js < webapp/patches/enketo-handle-no-active-pages.patch',
+            // patch enketo to fix repeat name collision bug - this should be removed when upgrading to a new version of enketo-core
+            // https://github.com/enketo/enketo-core/issues/815
+            'patch webapp/node_modules/enketo-core/src/js/calculate.js < webapp/patches/enketo-repeat-name-collision.patch',
 
             // patch messageformat to add a default plural function for languages not yet supported by make-plural #5705
             'patch webapp/node_modules/messageformat/lib/plurals.js < webapp/patches/messageformat-default-plurals.patch',