#17 AuthZ2: New AuthZ/Hierarchy with rows for implicit AZs

[Adam Franco]

Rework the Authorization and Hierarchy into a new 'AuthZ2' package that manages hierarchy-caused implicit Authorizations as rows in an implicit_az table. This should allow for much faster reading of implicit AZs at the expense of a slight slowdown in writing AZs.

[Adam Franco]

Logged In: YES
user_id=789554
Originator: YES

This is now mostly complete and in Segue2 testing.