[FEATURE] Add method to User model to get default external account.
[FEATURE] Add method to User model to get default external account.

whotooktwarden/gatewayd,Parkjeahwan/awegeeks,Parkjeahwan/awegeeks,xdv/gatewayd,whotooktwarden/gatewayd,crazyquark/gatewayd,crazyquark/gatewayd,zealord/gatewayd,zealord/gatewayd,xdv/gatewayd