Out with the old features, in with the new
Rasterizer Callback no longer gets Geometry back

Mostly because it's pointless, when Callback is passed in, geometry is
in scope. Therefore you can always close over it.
add implicit conversion Feature to Geometry
core-test pass, some ignored due to found bug
Reworked SRS methods to better fit proj4j

Also things compile
Merged in upstream, fixed IDW test.
Merge pull request #1 from lossyrob/feature-integration

Feature integration
Merge pull request #789 from echeipesh/feature/geojson-integration

geotrellis-feature integration into core