WAB attribute table widget - export to csv - xy coordinate unit configuration

Idea created by MHOOLE_governmentofbc on Jul 24, 2017

    Context:  When exporting a point dataset to csv using WAB's attribute table, AGO appends an x and y field and populates with coordinates based on the data's spatial reference.  There is no option to configure the output units for x and y.  The default seems to be web merc coordinates in meters.  We'd like to be able to configure the widget to export the x y coordinates in decimal degrees, a format that our audience can use without needing to do a translation.