Purpose
To detect the hotkey and then the slot that a unit is stored in and/or the unit 
that is stored in a slot within a hotkey for any player. 
Math
The total amount of units that can be hotkeyed
is 12.
There are 9 hotkeys in existence.
12 * 9 = 108 
108 is the total amount of EPD values for each
player.
	If we want to check if there's a unit in the
	seventh slot within the hotkey CTRL+0 for
	Player 1, 
	-10561 + 7 = -10555.
	If we want to check if there's a unit in the
	first slot within the hotkey CTRL+1 for Player
	1,
	-10561 + 12 = -10550.
	If we want to check if there's a unit in
	the first slot within the hotkey CTRL+0 for
	Player 2,
	-10561 + 109 = -10452.
12 * 9 * 8 = 864
864 is the total combined number of all players' EPD
value.
	We can check any slots within any hotkeys for 
	any player to detect if any unit exist. 
		At least 1
	We can check any slots within any hotkeys for
	any player to detect if no unit exist.
		At least 3749
	but what if we want to detect if a specific unit
	within the map is hotkeyed in a certain slot?
Unit alpha ID (Unit Entity)
Index #        Alpha ID
0	       2049
1	       3748 [+1700]
2	       3747 [-1]
3	       3746 [-1]
Confused? Hint: http://www.staredit.net/topic/14226/ (Read Section 6)