sbt/sbt — pull request #1529 by jsuereth (2014-08-13 18:09:32+00:00)
Title: An attempt to speed up travis CI by unziping a pregenerated ~/.ivy2/cach...

...e file.

Also includes the script to generate a new tar.bz2 which we should do anytime
we bump revisions significantly.

Review by @eed3si9n