Eliminated field is_active from Project model fixes #112

Having to activate and publish and project through the
admin interface was clumsy at best. Any projects that is
published is now indixable. Fixed related methods and test
to this field.
Merge remote-tracking branch 'origin/master' into issue112

Conflicts:
	website/projects/admin.py
Merge pull request #120 from rapidsms/issue112

Solves the ambiguity of having an is_active field and a status field