Don't request MongoDB recordStats

Disables the recordStats output which was introduced in MongoDB 2.4 and
causes a read lock, which can slow down agent execution and have an
effect on the mongod server itself.

http://docs.mongodb.org/manual/reference/command/serverStatus/#server-st
atus-recordstats

Requested in https://serverdensity.zendesk.com/agent/#/tickets/857
ensure we don't process rabbit if no creds are present
fix typo for if
update default url for rabbit
Merge branch 'record-stat' of github.com:serverdensity/sd-agent into develop
Bump version number for release
Merge pull request #66 from serverdensity/develop

Merge latest to master for release