Final library modularization for 2.11

The continuations plugin and library moved to https://github.com/scala/scala-continuations.
The Scala Swing library moved to https://github.com/scala/scala-swing.

They will still ship with 2.11 (albeit unsupported), but may disappear in 2.12.

TODO: add deprecation to CPS plugin over at https://github.com/scala/scala-continuations.

review by @gkossakowski

NOTE: I've moved the java7 patches over to scala/scala-swing as well, which means we're one step closer to building master on java 6 and 7 without modification. I noticed I missed a couple of changes to partest javaagent in the java7 branch. It would be good to port those over, and to see if we can get rid of the java7 branch all together in scala/scala.