Bump to Scala 2.9.3 and v3.0.1

The current build fails due to a missing dependency:
https://travis-ci.org/twitter/cassovary/builds/8979739

[error] (*:update) sbt.ResolveException: unresolved dependency: org.scala-tools.testing#specs_2.9.2;1.6.9: not found
[error] Total time: 32 s, completed Jul 11, 2013 2:20:53 PM

I suggest bumping to 2.9.3 which has the correct org.scala-tools.testing dependency (no idea why they didn't bother publishing a 2.9.2 version).

Signed-off-by: Chris Aniszczyk <zx@twitter.com>