Move GELF observer back to formatters, because everything is GELF formatted no matter what
Only configure graylog and airbrake if they are installed, and warn if there is a config for them but they are not installed
Remove txairbrake and txgraylog from requirements.txt
Add opt-requirements to bundle.sh
Remove extra verbs
Remove more verbs
Merge pull request #234 from rackerlabs/remove_tx_requirements

Remove tx requirements