REMORSE: Differences from original game when controlling Thresher cannon

[mduggan]

When controlling a turret (thresher cannon), the original Crusader: No Remorse does not provide crosshairs and only allows rotation to the pre-defined directions. This limits the effectiveness of controlling them as you need to catch an enemy in one of the set angles.

In ScummVM, robot control is implemented as an extension of CrusaderMoverProcess, so all robots get the smooth rotation and crosshairs that the Silencer gets. This is a small difference, but to perfectly match the original we should not apply these features when an NPC id other than 1 is being controlled.

[bluegr]

This looks to be a good candidate for a game option, where the player can enable this behavior as an enhancement over the original