Add Summary Widget to ArcGIS Online Web App Builder

Idea created by dcarpenter@hydro.mb.ca on Dec 11, 2014
    Implemented
    Score110
    Add an 'out of the box' widget to the ArcGIS Online Web Application Builder that is the same as the Summary widget currently in the Operations Dashboard for ArcGIS.  This widget is really handy for quickly configuring and then displaying total counts based on an attribute, averages, etc.