Massive Changes - See Description

Decided to go from two different content types for Employers and Organizations to one content type. The one new content type is employers_orgs_content_type.

Updated all other files that depend on the old types.

Changed image style name to represent that it is not just 200px wide but also high.

Also added Leaflet Markercluster module and library.

I hope this all transitions nicely to DEV where all this, plus dummy content existed...

Signed-off-by: Joe Whitsitt <joe-whitsitt@uiowa.edu>