* Move the authorization handling from pjproject to Asterisk
* Sync cached auth info between REGSITER and INVITE

Sync between REGISTER and INVITE happened while:

1. Got challenged, Sync to the other auth_sess;
2. before registration, Sync the latest info from INVITE to REGISTER;
3. after registration, Sync the latest info to INVITE.

Generally registration will do the active Sync(as 2,3), INVITE will just use what it has
in the auth_sess. nextnonce changes only applied into its own auth_sess, as registration
do the active sync, it will be synced to the other before use .