Added easy access to minor tick properties (Pierre G-M)
fixed mollweide
fix Antarctica for moll,robin and sinu (moll still broken)
remove debug code
Basic numpification, reformatting, some refactoring
remove use of ravel
added readme and exercise template
only read in state, country and river geometries when draw method invoked.
fixed for map projection regions that are not polygons in lat/lon coords
fix unit changes for errorbar_limits code
