ensure that hat wearers can fork hats and a hat tree

[spengrah]

the DAO (the wearer of the topHat) owns the authorities & powers it delegates to various hats, so those authorities and powers should not be forkable. However, the structure of the delegation and "hat tree" should be forkable and able to be (easily?) duplicated under the control of a different topHat.

[spengrah]

might be facilitated with batch create and batch minting

[spengrah]

batch create and batch mint would also facilitate templates and recommended frameworks for starting with hats from scratch

[spengrah]

Facilitate this by bringing back...

• createHatsTree
• batchMintHats

[spengrah]

addressed with #61 and #56

[spengrah]

Re-opening this based on a conversation with @topocount, who suggested a new approach:

Create a function that creates a new tophat that at first simply points to an existing hat in another tree, allowing users to later re-create the existing hats below it under the new tophat. This would enable cheap and flexible forking.