test : user name, team name, project name could contain [a-zA-Z0-9_-]

	modified:   projects/models.py
	modified:   projects/tests/test_project_manager.py
	modified:   teams/models.py
	modified:   teams/tests/test_team_manager.py
	modified:   users/models.py
	modified:   users/tests/test_name.py