Add Ownable Concern

Give projects and collections a polymorphic belongs_to relationship
to their owner. Convert user relations to those models to have
polymorphic relationship.
Add tests for is ownable

Allows projects and collections to be owned by either users or groups
closes #5
Add Nameable concern for unique uri names
Add uri name specs
Add to_param methods for urls
Add routes for the api

Conflicts:
	db/schema.rb
Merge branch 'feature-ownable'
Merge remote-tracking branch 'origin/feature-named_urls'

Conflicts:
	app/models/collection.rb
	app/models/project.rb
	app/models/user_group.rb
	db/schema.rb
	spec/models/project_spec.rb
Merge remote-tracking branch 'origin/feature-api_routes'
Update db schema
Correct projects to collections
Remove project diff lines
Transferring blueprint from apiary.io
Add mysql native dependency
Add documentation links to the readme