fixed scamr.local.mode bug with CDH5 MRv2
removed unused cdh3/cdh4 support
removed unused scala 2.9.x support, cleaned up deprecation warnings, use 2.10-style string interpolation
A fix for issue #5: job client resource leak
added support for user callbacks that get invoked at the end of an MR job
Removed MetadataWriter from job run
Merge master into SkipWritableChecks and make Metadata a callback