Oauth token renewal for offline backend

[forslund]

Currently the oauth-token is just read from the db without any check if the token is still valid. If the token is expired it should be refreshed automatically AND there should probably be a way to force the refresh if there has been some UTC-shenanigans.

I wonder if this should be offloaded to the oauth PHAL plugin instead of a direct db-call since the oauth PHAL already has the OAuth dependency?

[forslund]

@JarbasAl was this resolved in #65?