Wrapping up common input errors and presenting less-scary messaging

plus some other random cleanups.  Why not?!
Staying 1.8.7-compatible
Whoops meant to update email notifications
Cleaning up the build matrix a bit as well
Cleaning up JRuby dependency situation
Trying to figure out why the gem install fails on Travis JRuby
Overriding the correct step is a handy idea
Le arrrrgh
Mole <-> whack
Debugging requires DEBUG
Trying to ignore failures on JRuby

since it appears to build and install correctly *sometimes*.
Removing comment since I don't want to put it everywhere this is done
Normalizing error messages
Merge pull request #2 from modcloth/common-input-error-cleanup

Common input error cleanup