working toward geo
begin running tests
first geo test is passing
Lots more work on geo stuff.

* Fixed some coding errors
* Use native structs instead of objects to hold points/rects
* Made bounds test (in SQL query) use half-open intervals
* Made unit test pass.
Switch to emitting geo point as the key in a regular emit() call.
Added public API on CBLQuery to do a bounding-box query.
GEO: Added support for bounding-boxes.

* Use CBLGeoRectKey to emit a bounding-box as a key.
* CBLGeoJSONKey now understands rects.
* CBLQueryRow now has a boundingBox instead of a geoPoint.
GEO/FTS: Minor fixes