add 2 subclasses of RuntimeException, one to be thrown when there is a mistake in the arguments for a job, and one to be thrown when something is not supported in the current mode. although runtime exceptions are typically not supposed to be caught/handled this allows for nicer error messages to the user if one of these 2 errors is thrown (for example this could be done in Tool, not yet implemented)
pass message for new RuntimeException subclasses into super constructor
Merge pull request #860 from tresata/feat-exceptions

add 2 subclasses of RuntimeException, one to be thrown when there is a m...
Fix small bug in Stats where custom groups for counters were ignored.
Merge pull request #866 from daisyzhou/develop

Fix small bug in Stats where custom groups for counters were ignored.
Update scald to more robustly look for scala lib jars
Fix whitespace per Ian's comments
Merge pull request #867 from twitter/jco/fix_travix_via_scald

Update scald to more robustly look for scala lib jars
Merge remote-tracking branch 'origin/develop' into jco/joinWithTiny_bug