Add ProGuard exceptions for dokka using Grammar-Kit.
JS backend: fixed crash when use lambda or local function inside enum method.
JS backend: mangling JS reserved words.
JS backend: added tests for reserved words.
Improve Streams implementation for performance and validity (based on JMH research)
Add more tests on streams and move relevant code from old iterators tests.
Minor: code formatting
Add 6 standard charsets.
Rename encoding to charset for consistency
Unify charset-related APIs to use Charsets.UTF_8 as default. (Manual merge of PR#491)
Minor cleanup.
Make UTF-8 default for delegated java.lang.util functions. Convert getBytes() to toByteArray() to make it clear of copy operation.
Add Typography constants.
Refined merging logic #KT-5844 Fixed

If merging primitives of different integral types (e.g. I and Z) return
INT.
Else return UNINITIALIZED_VALUE