These apply if mysqlUserFolder is used as GRUF source for users:

(1) mysqlUserFolder has to use basic authentication. Reasons:

	a) if mysqlUserFolder uses cookies, it has to raise a login form, this 
		will break multiple user sources of GRUF, and possibly something else.

	b) GRUF will call authenticate () instead of validate () and this is a bad
		place to raise a login form.

(2) mysqlUserFolder will not setup roles from the MySQL database inside GRUF.
	In order to use MySQL roles, they have to be created manually.

(3) It is possible to create users using GRUF management screen.

(4) Don't use mysqlUserFolder as the group source - this is not tested. 
Anyway, I don't see much point in doing this.

(5) Option AUTO_CREATE_ROLES should be set inside cfg.py. This will autocreate 
in the database all GRUF special roles (used for managing groups).