Separated deprecated functionality from AbstractDataSource to
AbstractDataSource_old

Change-Id: I8a1902ceab188b3c312c9dc5dab213d5fe86dc04
switched to StandardLib.sort()

Change-Id: I169fe0d8bc411a7ae2ceb1df1cd3475d5a5e3d88
Implemented GeoJSONDataSource.  Not tested yet.

Change-Id: Id58c5d73e32b58d17484b2c6994d24201e1a9d28