`APlayer` and `ATrader` represented player and trader (`ShopVolume`)
with a single object instance. Such design, if used for all actors,
could have led to mutitute of problems rooted in need to find that
single object for any given native actor: we'd need to store
object-actor pairs separately and look through pairs lists, which is
hardly a sane design.
Now Acedia switches to a different design, where a single in-game entity
(i.e. actor) can have several interfaces referring to it. All equaly
valid. Refactoring `APlayer` and `ATrader` into `EPlayer` and `ETrader`
is a first step in that direction.
I shamefully ended up doing another mega-commit, because a lot of things
needed to be redone at once and it was easier that way on me. No one
really consistently tracks what I'm doing with these commits anyway.
This adds a whole bunch of code to deal with proper clean up for Acedia,
so it doesn't crash on map change and also replaces old event/listener
system with new signals/slots one.
This is a giga commit, something that should not really be done with
git, but I messed up.
This commit brings a great amount of changes, most important is
reworking `TextAPI` and alsmost complete replacement of `string` with
`Text`/`MutableText`.
Another huge change is introduction of command system that allows to
define commands in a centralized manner, handles auto-parsing of
their parameters and auto generates help info.
Lastly, JSON data types were replaced with new
`DynamicArray`/`AssociativeArray` that are better designed and more
generic.
Refactors `User` to simply store persistent data, while making `APlayer`
represent a connecte playr with appropriate links to `User` and (in
future) his in-game pawn representation.