Add mention of CartoDB support in pgraster input plugin code
Merge pull request #2372 from strk/2.3.x-pgraster-credit

Add mention of CartoDB support in pgraster input plugin code
travis: another attempt at getting both gdal+postgis going - refs #2353
backport geojson plugin fixes from master - refs #2319 and 2367
travis: re-enable devel for proj + image libs
Merge pull request #2380 from mapnik/travis-gdal

Travis gdal
Merge branch '2.3.x' of github.com:mapnik/mapnik into gyp
disable CTP compiler for now (only needed for c++11)