Re-enable IE9 sauce tests
Configure local sauce tests

Provide configuration and documentation for running sauce tests against
a local ilios install.
Activate windows 8 IE 11 sauce tests in travis
Activate OSX safari and chrome tests
Reorder travis matrix for sauce

Since sauce limits us to 3 windows and 3 mac VMs it makes sense to
alternate the travis matrix.
Merge pull request #625 from jrjohnson/iesauce

Sauce and Travis improvements