Complementary remove functions

Created a set of complementary functions which remove each type of dire hook. As well, I added a function remove the supervisor hook altogether from the target function. By keeping it a separate function, users now have the flexibility to add and remove all dire hooks at runtime, while retaining control over whether the function still uses the baked-in supervisor. This also means that a function which had a with-* bang method applied can disable the baked in hook while retaining the registered hook.

By the way, I changed the key being used to register the robert.hooke hook. It was currently using a non-namespaced `:key`. I changed it to a namespaced `::supervisor-hook-key` which should play nice with any app that uses robert.hooke for anything aside from dire.

It's all pretty thoroughly tested, but if you think of any test cases I missed, I'd be happy to add them. Give it a spin!