Update changelog

Changelog.md

@@ -1,11 +1,26 @@
 ## 0.6.0 / not released yet
-  * Removed `extendNodeEncodings()` mechanism. It didn't work in Node v4+ and was deprecated 5 years ago in v0.4.12.
-  * Reworked Streaming API behavior in browser environments to fix #204. Streaming API will be excluded by default in
-    browser packs to save ~100Kb bundle size, unless enabled explicitly using `iconv.enableStreamingAPI(require('stream'));`.
-    * Added a test for this behavior as a separate package in ./test/webpack folder and added a job for it to Travis CI.
-  * Minor updates to README.
-  * Switch from instanbul to c8 for code coverage.
-  * Added getEncoder/getDecoder to typescript definitions (#229).
+  * Updated 'gb18030' encoding to :2005 edition (see https://github.com/whatwg/encoding/issues/22).
+  * Added `iconv.getEncoder()` and `iconv.getDecoder()` methods to typescript definitions (#229).
+  * Added `iconv.preloadCodecsAndData()` method to help rare cases where the filesystem is unmounted/
+    chrooted after initial import, making lazy loading impossible (see #118). This function will 
+    eagerly load and cache all required modules and data files. It also works for older versions of 
+    iconv-lite deeper in the package tree (provide target module as argument).
+  * Removed `iconv.extendNodeEncodings()` mechanism. It was deprecated 5 years ago and didn't work 
+    in recent Node versions.
+  * Reworked Streaming API behavior in browser environments to fix #204. Streaming API will be 
+    excluded by default in browser packs, saving ~100Kb bundle size, unless enabled explicitly using 
+    `iconv.enableStreamingAPI(require('stream'))`.
+  * Switched Streaming API to lazy loading to save import time and memory for projects that don't need it.
+  * Updates to development environment & tests:
+    * Added ./test/webpack and ./test/preload internal packages to test complex new use cases that need 
+      custom environment. They are tested as separate jobs in Travis CI.
+    * Added 'benchmarks' folder with simple benchmarks for performance and load time.
+    * Updated generation code for the new EUC-KR index file format from Encoding Standard.
+    * Fixed semver version to 6.1.2 to support Node 8.x (by @tanandara).
+    * Capped iconv version to 2.x as 3.x has dropped support for older Node versions.
+    * Removed Buffer() constructor in tests (#197 by @gabrielschulhof).
+    * Switched from instanbul to c8 for code coverage.
+
 
 ## 0.5.1 / 2020-01-18