Create App.js

Simplified version of of the app.js for Boundless OpenGeoSuite-SDK ol3view. The code essentially creates a simple Basemap from the local geoserver with a group layer of a university campus composed of layers (buildings, shrubarea, sodarea, and basemap outlines) then as overlays it has the layers (shrubs, trees) As it stands Popups do not work but will be implemented in the next release.