Moving fixture into standalone module and new module tests.utils
Moving neighbors tests to tests/integration
Star/Unstar projects
List fans and starred projects

List project fans:

     /projects/<project id>/fans
     /projects/<project id>/fans/<user id>

List user starred projects:

     /users/<user id>/starred
     /users/<user id>/starred/<project id>

Also a "star" field with the stars count of a project is included in the
project detail and list responses.
Merge pull request #43 from taigaio/stars

Star projects
Remove wrong usage of BASE_DIR on settings.
Minor fixes on tags sql file.
Load tags sql on connection is created on tests.
Remove global imports from test factories.
Remove unnecesary userstory model import from project models.
Minor changes/improvements on exceptions tree.
Cosmetic fixes on project serializers.
Remove global project import from stars service.
Improve queries and transaction management for better testability.
Add method for attach stars count to projects queryset.
Cosmetic changes on stars __init__.py file.
Improved get_queryset methods on project api resources.

Attaching stars count to querysets.
Fix unhandled not found exceptions on get starscount on project serializer...

... using annotated stars count value instead of obtaining stars object.
Remove unnecesary Response usage on wiki page api resource.
Fix stars tests.