CHANGED: in newer version of PostGIS, structural changes have been made

* the geometry_columns table is now a view
* relevant tables (geometry/spatial_ref_sys) can reside in own schema
Merge pull request #42 from hendrikstier/78cd6bec104a391ca16ab4e04b4fcecaa440680b

database.rake modified to suit PostGIS 2.0+
Put in some requires to try to fix JRuby
Refactor the database rake tasks to add a db:gis:setup task.