Ignoreline parameter for ignore any line

I put ignoreline (-l) parameter for ignore any line from "df" output. With this you can ignore a disk by any parameter.
Create a parameter file for config parameters

- Ruby 1.9 tested
- XMPP and Google Hangouts problem solved (see notes)
Graphite mutator created

I extend OnlyCheckOutput mutator specialy for Graphite. This mutator only send event output (so you don't need to use OnlyCheckOutput) and change parameter name if it is hostname for better view in Graphite
fix for rubocop problems
handle empty lines in /proc/stat

- sometimes there is empty line in /proc/stat and we don't need this lines.
- some additional parameters set what I found in /proc/stat
Removed occurrence handler since sensu-plugin already has it
Removed custom ruby path
Merge pull request #283 from rafaelmagu/master

Removed occurrence handler
Merge pull request #280 from tarhelypark/master

check-disk and gtalk modifications