Restyling the handler system.

Long story short: I'm setting the wheels in motion for a better version
of Paul's handler. There's a lot of planning to do but my goals are easy
implementation & use as well as avoiding multiplying the number of
interface LinkedLists by four. Hopefully I won't need more than 4 TOTAL
linked lists, but if I do end up needing 1x the interfaces, it will at
least be a big improvement.