Add HTTP-based PID minter

- Add support for authenticated PID minter services
- Makd master.xml spring config file to bundle config files and avoid wildcard include

Resolves: https://www.pivotaltracker.com/story/show/70678050
Passes the user session through to subclasses that implement the role-based permission callback.

- This is needed for the XACML delegate, for instance.

Relates to: https://www.pivotaltracker.com/story/show/70771806