Add a class for custom Json renderer.

The custom renderer adds the ability to handle unexpected responses by checking
the value of the return value from the controller method.  This allows for
setting different http status codes (such as 404) instead of just the 400 or
500 that wsme allows.
Fixed Templates path in config
Initial HEAT template generation

Generates a HEAT template based on Tuskar objects.
Merge pull request #24 from slagle/json-renderer

Add a class for custom Json renderer.
Merge pull request #26 from mtaylor/heat

Initial HEAT template generation work
Added Relation for Rack Resource Class
Allow setting ResourceClass on Rack
Merge pull request #30 from mtaylor/resource_class_on_rack

Allow setting and getting of resource class on Rack
Added 'location' attribute for Rack
Added default state 'unprovisioned' to Rack