More spatial query types

this is my first pass at writing the logic to make sure query spatial operator methods can accept both raw geojson geometries or LatLngBounds objects

1. added an internal 'isGeojson' check within Query itself
2. added a 'Geojson type to ArcGIS type' function in Util (because i needed something similar in my gp service plugin
rewrote within() to just call intersects (because they both end up making the same request)

let me know what you think.