Bump libspatialite to 4.1.0 and related package version 

Removed GDAL caveat because current GDAL and this spatialite work just fine.

Added CFLAGS for homebrew SQLite otherwise spatialite complains about mismatched version number in the header.

Does not include spatialite_gis and spatialite_gui because those require wx* and I can't get that to build on my machine