Updating docs
Adding RabbitMQ module to handle parameters
Adding parameters example
Merge pull request #2251 from chrishoffman/rabbitmq

Rabbitmq parameters module
for #2196 now gruopby module invalidates host cached variables so they can be reevaluated with new groups
Signed-off-by: Brian Coca <bcoca@tablethotels.com>
Merge pull request #2261 from bcoca/groupby_2186

now group by module invalidates host cached variables
Log tracebacks to syslog when using fireball mode.