Bringing Simba1500 Walker to Simba1400 (#67)

* refactor: added `Contains` methods to equipment and inventory.

I've also left a comment on the PR after the last commit because I forgot to mention TRSBank.ContainsItem().

Anyway, this has the same reasoning. This is optional but I would like to bring the SRL1400 API closer to SRL1500 API.

Old methods are kept and marked with a comment as deprecated so there's no downside to adding this.

This also brings documentation to TRSInventory which is nice :)

* fix: added deprecated warnings

also added more docs to inventory

* feat: Simba1500 TRSWalker backport

This update Simba1500 walker to simba 1400.

Simba rework credits go to Olly, I just made a few tweaks to make it compile.

There's also a couple of bug fixes I made and added a lot of documentation (maybe too much?).

OnWalkEvents were changed to update playposition and destination if the user wants

* Update walker.simba

osr.simba

@@ -74,6 +74,7 @@ end;
 {$IFNDEF SRL_BANKPIN_INCLUDED}         {$I osr/bankpin.simba}
 {$IFNDEF SRL_GRANDEXCHANGE_INCLUDED}   {$I osr/grandexchange.simba}
 {$IFNDEF SRL_DEPOSITBOX_INCLUDED}      {$I osr/depositbox.simba}
+{$IFNDEF SRL_WALKER_MAP_INCLUDED}      {$I osr/walker/walker_map.simba}
 {$IFNDEF SRL_WALKER_INCLUDED}          {$I osr/walker/walker.simba}
 {$IFNDEF SRL_STATS_INCLUDED}           {$I osr/stats.simba}
 {$IFNDEF SRL_EQUIPMENT_INCLUDED}       {$I osr/equipment.simba}
@@ -118,6 +119,7 @@ end;
 {$ELSE}{$ENDIF}
 {$ELSE}{$ENDIF}
 {$ELSE}{$ENDIF}
+{$ELSE}{$ENDIF}
 
 {$IFDEF SRL_HAD_HINTS}
   {$HINTS ON}