Initialization; Persistent, Lazy Filters

These commits introduce initialization hooks and solve the issue of filters being created on require.

The hooks were originally created to literally create the filter when it `stack-initialize` is called, but a re-implementation of filter access (prototyped by @Bruce-Connor) rendered this unnecessary.
The main difference here is the removal of the filtering logic. `stack-request-make` now assumes that your call contains all the information you want in it (sans the API key, since all requests should include it).