is_global == 1 don't work with postgresql

With the current trunk

In keystone/backends/sqlalchemy/api/tenant.py :

  189 filter(endpointTemplates.is_global == 1)

Give this error with postgresql as backend:

  File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/default.py", line 299, in do_execute
    cursor.execute(statement, parameters)
ProgrammingError: (ProgrammingError) operator does not exist: boolean = integer
LINE 4: WHERE endpoint_templates_1.is_global = 1 UNION SELECT endpoi...
                                                                                                       ^
HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.

I think True should be use instead of 1