Rebuilt dependencies with java 7 bytecode.

It should all work with java 7 now. Java 6 is within reach
but not within my current motivation to pursue.

Bootstrap compiler 1.0.0-M5 is java7 clean.

For future reference, you can choose a different bootstrap
compiler than the one specified in build.properties like so:

  sbt -Dbootstrap.module=org.scala-lang:scala-compiler:2.11.2 package