Changes to the icon manager to match Mapnik better.  Can now start with JSON or XML based Mapnik file.  Marker style matches Mapnik a bit better.  Added Maki icons to project.  Starting to add Mapzen vector tile source.
Can now force label to stay upright on the screen.
Allow users to set the default font used by text.  Upright text implemented in layout logic.
Cleaned up marker name logic
Title fix.
Fixed an opacity interpretation problem.  Now parsing rgba colors.
Merge, module cleanup
Updating submodules.
Fixed submodule reference to clipper
Old reference to clipper
SF roads example now working correctly (and quickly).  Fixed an overlay disable problem.
Updating for 2.3 distribution
Disable and removal problem with wide vectors.
Made default marker size changeable.
Fixed heading output
Merge branch 'develop_2_3' of git+ssh://github.com/mousebird/WhirlyGlobe into develop_2_3
Merge remote-tracking branch 'upstream/develop_2_3' into develop

Conflicts:
	WhirlyGlobeSrc/WhirlyGlobe-MaplyComponent/src/MaplyMapnikVectorTiles.mm
fix FMDB missing after merge