Use java executable from $PATH
Remove user-env-compile instructions
Merge pull request #62 from heroku/sbt-vendored-java

sbt should use java on PATH
Merge pull request #63 from heroku/remove-uec-mention

Remove user-env-compile instructions
Add support for SBT 0.13.1
Merge pull request #66 from matt-thomson/master

Add support for SBT 0.13.1
Merge remote-tracking branch 'upstream/master'