Small changes in AccountSpec
Move AccountFactory into the support package
Rework the controller auth API
Require SuperUser scope in Api, App controllers
Simplify /accounts/[UUID]/access_tokens

Now, only creates access tokens with Admin scope, for requests made with Auth
scope
Implement GET /access_tokens...

as a replacement of GET account/:guid/access_tokens. Now, to get the list of
an access tokens, an Admin access token for that account is required.
Remove pointless auth in GET /access_tokens/:guid
Implement POST /access_tokens

Creates access tokens for the account associated to the authenticated access
token, as long as that access token has Admin scope.
Add authRedirectUrl to App model
Store access token authorization data
Return authorized AccessTokens where appropriate
Return an authorized Account where appropriate
Remove unneeded imports from AccessTokenController