Merge pull request #374 from mozilla-services/features/no-stat-prefix

No longer require that stats be prefixed w/ the 'stats' namespace.
Fix sandbox compiler warnings when using -Wall
Issue #384 Add support for sub-packages in add_external_plugin
Issue #384 Updated the docs
basic multidecoder should work now
Merge branch 'dev' into issue_384

Conflicts:
	CHANGES.txt
Merge pull request #382 from mozilla-services/warnings

Fix sandbox compiler warnings when using -Wall
Merge pull request #387 from mozilla-services/issue_384

Issue 384
Bump whisper-go revision to fix aggregation (issue #379).
added default Catchall logic to the MultiDecoder in the event that a message was not properly decoded by any contained decoder.
send log messages to the standard logger if a DecoderRunner is not available
bind the name of the decoder into the MultiDecoder
check that MultiDecoder loads into it's own DecoderWrapper
added a test to verify that a MultiDecoder with a single subdecoder works as expected
append ".catchall" to the Message.Type prior to re-injecting the pack into the pipeline
added test for catchall for the MultiDecoder
added testcase to verify that if Catchall is disabled, MultiDecoder will log an error and recycle the PipelinePack.
re-enabled all pipeline testcases
Merge branch 'dev' into features/multidecoder

Conflicts:
	pipeline/decoders_test.go
added docs for MultiDecoder
Merge branch 'dev' of https://github.com/mozilla-services/heka into dev
Issue #263 LogfileInput parsing improvements

- Fix the file handle leak in file discovery
- Update the journal to store the location and length of the last record
  (not backwards compatible, existing journal files will fail to load and a new one created)
- Add the regexp parser
- Keep the token parser since there are some performance benefits (10-15%)
over the regexp parser (mainly do to the final conversion from byte array to string)
- Remove the Logline struct and use a pipeline pack instead. This is cleanup and
preparation for the protobuf parser which needs access to the pack and message)