Mongo removal: Remove the validate=True arg to obj.save()

all callers were forced to use validate=True anyway. So
remove this useless stuff.

mediagoblin/gmg_commands/users.py

@@ -55,7 +55,7 @@ def adduser(args):
         entry.pw_hash = auth_lib.bcrypt_gen_password_hash(args.password)
         entry.status = u'active'
         entry.email_verified = True
-        entry.save(validate=True)
+        entry.save()
 
         print "User created (and email marked as verified)"