"Target next objective craft" command can reveal unidentified mission objectives

[Rob Pilkington]

In TOD2M8 "Stop Hyperdrive Replacement" (max1), the "target next objective craft" command will immediately target the unidentified freighters.

The intended way to play the mission is to identify the two freighters in order to determine which ones must be taken out to complete the mission.

I haven't checked the mission in an editor, but I'd assume the target freighters are each in their own flight group.

A better behavior would be to cycle through all potential (i.e., unidentified) targets of that craft type (and possibly IFF?) until they have been identified. Identified craft that are not the objective can be ignored as they are confirmed to not be the objective.

(Note: the command continues to cycle through all craft within a flight group even after the special craft has been identified. The behavior for craft within a flight group should be the same as when there are multiple flight groups of the same type.)

[Ras Talon]

This affects at least two more missions:

TOD2M11, you need to find the Tantive IV by inspection, O key reveals it right away.

TOD4M19, you need to find Corvette with shield X, but O key reveals it right away. (It was possible to find it in the original right away by counting 'Next target' keypresses.)

[Xwvm Art]

Change Target Next Objective Craft behavior so that it doesn't spoil mission objectives (fixes #347)

→ <<cset e0d64333deb3>>

[Rob Pilkington]

fix committed and tested