CDB-3079 enforces postgres user in preparation script and changes travis config to use postgres 9.3, postgis 2.1 and mapnik 2.2.0
CDB-3079 testing with mapnik v2.1
CDB-3079 install mapnik and gdal before adding cartodb repositories
CDB-3079 coming back to initial travis config
CDB-3079 testing latest 0.7.x mapnik version
CDB-3079 testing mapnik 1.4.5 version
CDB-3079 testing mapnik 1.4.5 version + postgres travis config
CDB-3079 trying mapnik v2.1.0
CDB-3079 forcing mapnik version for tests
CDB-3079 postgres addon from travis as basic setup
Merge branch 'CDB-3079' of https://github.com/CartoDB/Windshaft into CDB-3079

Conflicts:
	.travis.yml
CDB-3079 creating postgis extension before anything else
CDB-3079 creating postgis extension for database template_postgis
CDB-3079 add postgis extension to test database
CDB-3079 install postgis after mapnik
CDB-3079 use before install and before script
CDB-3079 just another attempt :-(
CDB-3079 forgot to install postgres+postgis
CDB-3079 install postgis without db
tries with mapnik 2.1 and node-mapnik 0.7.28