Extracts RouteAdapter

Extracts adapter inner class from RouteFragment into its own file to improve readability and testability.

* Renames RoutesAdapter -> RouteAdapter
* Creates com.mapzen.route package
* Moves  RouteAdapter from inner class to its own file
Moves RouteFragment into com.mapzen.route package.
Adds RouteAdapterTest
Breaks up RouteAdapter$instantiateItem(...) for readability.
Migrates adapter specific tests from RouteFragmentTest to RouteAdapterTest.
Updates distance remaining for flipped instructions.

Updates the distance to the next instruction based on current location in routing mode.
Merge pull request #165 from mapzen/chuck/live-update-distance-to-turn

Updates distance remaining for flipped instructions.