Updatable Component System

[exectails]

There are always things in characters and monsters that need to be updated in regular intervals, such as buffs, regens, etc. I'm currently working on this in the add/component-system branch.

In addition to being able to add components to characters and monsters, that are then able to interact with these entities, and update them, I think we might want to embrace the entity component system more in general, as it might be well suited for ToS, where characters and monsters need many of the same features, but not all of them. And also, not all monsters need all features, because NPCs and props are "monsters" as well.

[exectails]

The basic system has been added, but I'll leave this open for the moment because I think we might want to go further with it. I'm still thinking about that, however.