logstash 1.4.0

Upgrades logstash formula to 1.4.0.
Due to radical distribution changes upstream, we need to inreplace a few lines
to get it to run from the Cellar.
logstash 1.4.0

Upgrade logstash to 1.4.0

* added test suite, will test a simple log flow
* added caveats with link to documentation for beginners
* passes brew audit
logstash 1.4.0

* KNF
* remove EOF marker from second test to help build-bot parse it

Build from --HEAD breaks homebrew downloading conventions a lot,
so it was added then removed before commit.  Upstream logstash
needs work on their build system before we should consider it.
logstash: add 1.4.0 bottle.