upgrade modules to use plugin 2.x

[SethTisue]

PRs

• scala/scala-parallel-collections#57
• scala/scala-java8-compat#134
• scala/scala-async#215
• scala/scala-partest#116
• scala/scala-collection-compat#184
• scala/scala-parser-combinators#190
• scala/scala-swing#93

issues

• scala/scala-xml#278

[SethTisue]

scala-xml issue remains open. other repos completed.

[SethTisue]

forgot about scala-continuations before, but it's done now: scala/scala-continuations#47

and scala-xml is done now too, scala/scala-xml#291