Typo
SBT bump
Remove boot properties
Merge pull request #72 from heroku/play-2.3

Play 2.3 Support
added support for release candidate versions of sbt
Improved sbt version regex to accept more types of versions. improved tests
added a publish script
increase thread stack size to 4M during compilation to avoid StackOverflow errors
moved the sbt script creation outside of the if block to force. also removed sbt.boot.properties from its options
split the sbt tasks into update and compile on the first run, so artifacts can be cached
add codes to download a pre-built ivy cache to prime the local cache
split the play ivy cache into packages by version to reduce download and cp size
renamed sbt cache files
added a play version test
added a negative test for priming ivy cache
changed sbt script to a heredoc
renamed get play version method
fixed a silly bug in checking play version
fixed sbt command so it never prompts for retry/quit/ignore
added test for priming ivy cache for play apps