Fixed server crashing when the wall is upgraded when being repaired.

A possible fix to server crashes (changes to angel's heal).

Fixed high armor values making troll invulnerable after the latest dota patch.
Attempt to fix sometimes some elves and troll getting stunned indefinitely at the start of the game.

Abilities now have gold and lumber costs on top of ability icon.
Fixed building grid showing trees as buildable area.
A try to fix multiple troll bug (If multiple troll bug or wall glitch still happens after this update - please report).

Minor changes.

Attempted to fix wall glitch (Please report if they still happen).
Limited to 40 towers per player.

Reworked building building/upgrading logic, should be way more efficient.
Modified entity dying logic (Please report if wall glitches or troll respawning glitches still happen).

Fixed winter maps becoming black.

Added ability placeholders for max level troll hut and trader, so their abilities get the same hotkeys no matter what level the buildings are. (Should upgrade building ability be moved to an item instead?)
Abilities that don't have hotkeys will be given unused item hotkeys (Don't change your hotkeys after starting the game (you can shuffle items in your inventory)).
When gold wisps start building the gold mine they get deselected.

Reworked logic when units die, the change might have fixed elf's buildings not getting destroyed and not giving a choice for angel/wolf when elf dies.
Reworked troll invis.
Fixed allowing elves to blink outside the map.
Fixed troll swallowing items when he had full inventory and wolves tried to give him items.