Fix script. Add commands and a Sub-Manager

[fmerges]

I noticed script.py, not sure if this is deprecated or still in use...

Having the sub-manager will allow to do something like this in your main manage.py:

from flask.ext.security.script import manager as security_manager
manager.add_command('security', security_manager)

[coveralls]

Coverage decreased (-1.52%) when pulling c59af85 on fmerges:develop into c7d0ea9 on mattupstate:develop.

[coveralls]

Coverage decreased (-1.52%) when pulling ffb66ae on fmerges:develop into c7d0ea9 on mattupstate:develop.

[mattupstate]

This could potentially break things for existing users. Additionally, I'd like to revisit the commands when Flask ships with its new CLI tools.