init checking of a heka compatible raven plugin
updated test cases to play nice with the new protobuf headers used in heka-py
updatd testcases to use Protobuf encoding and removed some
lingering instances of the heka.senders namespace
* added mozilla-sandstone theme
* dropped epoch_timestamp as we no longer use logstash
* bumped to revision 0.6
* removed references to older metlog APIs
Merge branch 'features/heka_patch' into dev

Conflicts:
	README.rst
	docs/source/config.rst
	heka_raven/tests/test_heka.py
	required.txt
	setup.py