TravisCI: Enabled raster support
types: Added basic Raster type
test_functional: Added Ocean table

Make sure there are no errors when using the Raster type on PostGIS 2.x
__init__: Create indices for raster columns
Merge remote-tracking branch 'origin/master' into raster

Conflicts:
	.travis.yml
test_functional: Added insertion test for raster column
setup.cfg: Enabled output capturing for nosetests
tests: Added index checking functional test
elements: Added RasterElement class
types: Added result_processor() to Raster type

This transforms the SQL row output into RasterElement instances
functions: Added ST_Height and ST_Width functions
functions: Added ST_Value function
elements: Allow calling ST_ functions on WKTElements
functions: Added ST_AsRaster function
Merge pull request #32 from Turbo87/index-test

Added index checking functional test
doc: Disabled html_static_path variable

There is no need for this and it fixes a not-found warning on some
platforms
doc: Always use local version for sphinx build

This makes sure that the local codebase is used and not the one that might
be installed on the system.
types: Fixed typo in documentation
Merge pull request #34 from Turbo87/docs

Small documentation fixes/improvements
Merge remote-tracking branch 'origin/master' into raster