Fix tests on Windows by passing -usejavacp to the compiler used in tests.
Strip windows newlines when comparing test results.
Switch the sbt build to 2.11.4, but keep cross compilation for 2.10 and 2.11
Update to sbt 0.13.5 and gpg 0.8.3
Simplify our cross-compilation to just use scalaVersion.value.
Set fork := true to successfully run the tests with sbt.