Slack engine fix results
Slack engine fix results

* Changing the way results from the Slack engine are displayed in Slack, rather than dump the results into the channel as a message we upload as a file.  This way Slack handles displaying as much of the content as it can and the full results are still available.

* Change type of file to be yaml so Slack will format it nicely.

* removing code in master.py

* engine configuration is now a dictionary of dicionaries, updating docstring for slack engine

saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt