Add support for named/un-named regexp capture groups in the matcher
Merge branch 'dev' into features/message_matcher

Conflicts:
	pipeline/filters.go
Move some test helper init.
Puts control of the input goroutine into the InputRunner, which saves some finicky
boilerplate and gives us a slightly better chance to recover from panics. Also adds
LogMessage method to PluginRunner for consistent output when there's not an error.
Fixes UdpInput hanging on shutdown.
Waitgroup is handled by the InputRunner, no longer needs to be passed in to the
Inputs.
Add capture support to the matcher

- Added a second input channel to the FORunners to receive the PipelinePack and the Matcher
capture results
- replaced message_manipulation.go functionality with message_matcher
- updated the sandbox timer_event API to pass the time in (since the Lua clock is low resolution)
- updated the sandbox_filter to use the MGI for message injection, output is still TBD
Merge pull request #49 from mozilla-services/features/message_matcher

Features/message matcher
Merge branch 'dev' into features/run-plugins

Conflicts:
	pipeline/mock_outputrunner_test.go
	testsupport/mock_net_conn.go
update mocks
Start of sphinx docs for head.
Change filters and outputs to use `Run` instead of `Start` where the goroutine is
started and managed by the calling code in the Runner instead of within the plugin.
Also get rid of the separate InChan and MatchChan to simplify plugin implementation,
substituting w/ a `Deliver(pack *PipelinePack)` method on the runner that will wrap
the pack in a PipelineCapture and drop it on the input channel.
Slightly cleaner equivalent logic.
Merge pull request #48 from mozilla-services/features/run-plugins

Features/run plugins
Merge branch 'dev'