Minor changes on graphite plugin.

- Added metrics_format option to define the resulting format of the
  metric string that will be sent to graphite.

  example:

    graphite {
      host => "graphite.local"
      port => 2003
      fields_are_metrics => true
      include_metrics => ["foo"]
      metrics_format => "my.system.%{metric}"
    }

- added test suite for graphite plugin
add gem licenses
more licenses
add one more license
Merge pull request #414 from nickethier/LOGSTASH-569

LOGSTASH-569
Added support for IETF 5425 syslog parsing in grok.
Changes wrt. @jordansissel's comments on [my pull request](https://github.com/logstash/logstash/pull/415).
Merge pull request #415 from adesso-mobile/master

Grok support for IETF 5424 syslog parsing
Meh. Forgot one variable...
And another one :-( Working in the eve is a **bad** idea.
Merge pull request #416 from adesso-mobile/master

IETF syslog grok fixes :-(
- don't differentiate owner/contributor
- swap 'the bomb' for 'awesome'
- permit decimal values in :number validation
Replaced placeholder %{metric} with '*' as aligned with jordansissel
Fixed documentation of graphite output plugin
Merge pull request #395 from invadersmustdie/graphite-format

Minor changes on graphite plugin.
enhanced translate filter
some doc updates and typo fixes
blocking congestion check implementation for redis output
fix typo