Implements the new synchro of team members from odoo to GitHub

As discussed with @gurneyalex, the project teams will no longer hold all the
core committers. There will be an additional team for the core committers
assigned to each project. The edition of the team members will be done on odoo,
never on GitHub.

What will do this script:

* It considers odoo as the master, meaning that, for each team,
  it removes from GitHub all the members that are not members in
  odoo. Conversely, it adds the new members who have been added on odoo.
* It reports the users who should be added to a team but can't because their
  GitHub login is missing.
* Teams are matched using their name, it reports the teams not found on GitHub.

One side effect of the first statement is that odoo users who have not their
GitHub login set on odoo will be removed from the GitHub teams, so the first thing
to do is to fill in all the logins. Users that miss their login actually:

  Sylvain LE GAL
  Joël Grand Guillaume
  Eric Caudal
  Sandy Carter
  Rijnhart Stefan
  admin
  Nicolas Bessi
  Nhomar Hernández
  Sébastien Beau
  Vaucher Yannick
  Maxime Chambreuil

You will note the presence of the admin user, we could blacklist it but I
prefer to leave it because it should be removed from all the teams anyway.

Then, we must ensure that team names match on both sides. The odoo teams not
found on GitHub (normal for some of them):

  Board Tasks
  Connector CMIS Maintainers
  Local Belgium Maintainers
  Local Luxemburg Maintainers
  Local Mexico Maintainers
  Processes
  Product Maintainers
  Project & Services Maintainers
  Project Steering Committee
  Support
  Template Maintainers

We'll also need to have a new team "Core Maintainers" or "Core
Committers" assigned on all the OCA projects.

We probably want to setup a cron somewhere.