upgrade jvm-common to v3, to upgrade jdks
Merge pull request #36 from heroku/upgrade_jdk

upgrade jvm-common to v3, to upgrade jdks
change path to match whats in tar
Merge pull request #39 from economico/master

change path to match whats in tar
upgrade jvm common. take advantage of the stuff it does for us

made jvm-common download more like the other buildpacks
added docker runner, and some basic tests
removed mac setup stuff from docker script
updated tests for new default jdk
added some lein2 tests