Remove Play fork.

Scala 2.11 compatibility patches has been merged upstream.
Remove fork of json4s.
Merge pull request #17 from cunei/master

Adding bootstrapping config, and factoring out projects in a common file
Moving gkossakowski's patch to common-2.11.x.conf
Merge pull request #19 from cunei/grek-fork-less

Scala 2.11 patches to Play and json4s were merged upstream.
Remove scala-io fork.

Most changes needed to build scala-io with Scala 2.11 has been merged
upstream. The only remaining problem is failing scaladoc that I haven't
investigated yet.
Merge pull request #20 from gkossakowski/fork-less

Remove scala-io fork.