Transpose Google Apps API

[fishilico]

Polytechnique.org's current website syncs the password with the Polytechnique.org-provided Google Apps. This is configured in specific profile pages (https://www.polytechnique.org/googleapps). xorgauth needs to provide this feature:

• Save a GApps-compatible password in the database when the password change
• Enable users to choose between "same password as their account" or a different one
• Import this setting (and the password) from the current database
• Transpose the script which syncs the account credentials with Google in order to use the new database (this is probably the more challenging aspect)