[12444] Remove dropped SingletonImpl.h file from VC project files
[12445] Add const Group member iteration
[12446] Implement CONDITION_DEAD_OR_AWAY

Usage of value1:
* 0: return true if player is dead (or NULL)
* 1: return true if all members of player's group is dead (or no player)
* 2: return true if all players in an instance are dead
* 3: return true if the source-creature is dead
Usage of value2:
  if value2 is provided, then this is taken as range. if the player is outside of this range the condition returns true as well
[12447] Implement SCRIPT_COMMAND_TERMINATE_COND

This command is used to terminate a script execution based on a condition (from `conditions` table)
* datalong = condition_id
* datalong2 = fail-quest
* data_flags & SCRIPT_FLAG_COMMAND_ADDITIONAL terminate when condition is false. ELSE(normal case) terminate when condition is true