Add RBAC decorator and plugin

[davidolrik]

Role based authentication for use in plugins.

Included in this pull request is two decorators: rbac_require_any_role and rbac_require_all_role, and a "admin" plugin for assigning roles dynamically, and for being notified of people trying to use commands they aren't allowed to.

# User must have any one of the listed roles
@respond_to(regex=r'^my cool command$')
@rbac_require_any_role(['root', 'admin'])
def my_cool_comand(self, msg):
    pass

# User must have all of the listed roles
@respond_to(regex=r'^my other command$')
@rbac_require_all_roles(['role1', 'role2'])
def my_other_comand(self, msg):
    pass

Still needs docs and better error handling for edge cases.

[DonDebonair]

This is super useful! Needs docs indeed.

In my opinion, we could get rid of the rbac prefixes in the decorator. It's clear from the rest of the decorator names what it's doing.

[DonDebonair]

@davidolrik I'd still love to include this, but it still needs documentation. Are you planning to provide that?

[davidolrik]

Definitely!

[davidolrik]

@dandydev: I've added docs - let me know if it is enough, and if it is placed correctly.

[davidolrik]

I've also rebased it with master so it should be easy to merge.

[davidolrik]

Rebased with master.

[davidolrik]

Rebased with master.

[davidolrik]

@dandydev Are there anything more needed for this to be merged?

[DonDebonair]

Sorry for the super late response. I was switching jobs and have a new puppy that takes a lot of my spare time. This looks great and there's only one small change in the docs that is required before I can merge.

[davidolrik]

No worries =) - I have a Golden my self, which kind of puppy?

[DonDebonair]

A golden as well! <3

[davidolrik]

[DonDebonair]

What a lovely doggo!

This PR has turned out to be the most wholesome PR in my open source career so far ;)

[DonDebonair]

Merged!

[davidolrik]

Lets make more PR's like this then 😁