Merge pull request #226 from adriaanm/master

Fix more references to spec
Fix file extension in sources download
parentheses in url break markdown rendering, replace by %28 / %29
2.11.2 release

Release notes still missing
release notes for 2.11.2
Merge pull request #227 from lrytz/2.11.2

2.11.2 release
version number slip
Merge pull request #228 from lrytz/2.11.2-fix

version number slip
Scala: next steps