Merge pull request #17 from aanderson-usgs/SEISMICDESIGN-179

SEISMICDESIGN-179: GriddedDataFactory Null Handling
Merge pull request #18 from aanderson-usgs/SEISMICDESIGN-178

SEISMICDESIGN-178: Subscript second character for SS and S1 for all cases in output window
SEISMICDESIGN-189: Edit links for Documentation
Changed documentation link in summary tabs.
SEISMICDESIGN-187: Convert region-specific red map overlays to layers that can be toggled on/off
Added layerControl to RegionController object.
Merge branch 'SEISMICDESIGN-187' into 0.0.3-aanderson

Conflicts:
	src/htdocs/js/GlobalDesignApplication.js
	src/htdocs/js/RegionController.js