LBIdentity

[addisonhardy]

• Add a new LBIdentity class (Add LBIdentity class for integrating with identity plugins #7)
• Update bridge API user create view:
  • Use new LBIdentity.get method
  • Use normal Django model create method to create the user object
• In WCP:
  • Drop custom JPLPersonnel.user method and replace with post_save signal handler
  • In post_save handler method, call LBIdentity.get(identifier) to hydrate user attrs

[Scotchester]

Done in #7

[Scotchester]

Oops, actually only the first part is done.