introduce 'resource_url_prefix' settings
bugfix: two different resources can begin with the same string
I do not think I understood this code completely.

This tries to fix the following error:
If there is a namespace called 'communities' with the API path '/api/v1/communities/' it would be removed.

Is there any better way to handle this scenario? What existing URLs will this break?
Merge branch 'feature-group-resources-by-url' of https://github.com/lukas-hetzenecker/django-rest-swagger

Conflicts:
	rest_framework_swagger/urlparser.py