don't fail map if no NPCs are visible, fixes taxi-04 with 3 transfers

[cryham]

This fixes taxi-04 properly and all other taxi map issues: if NPCs arent visible (hidden in caves) map will fail, with no reason, this was a bug.
Feel free to restore taxi-04, it will work now, with 3 transfers as before. 5cac237

[mgerhardy]

please remove the commented code. if it is wrong is has no real value here. Even though I wonder how can we lose such a map now?

[cryham]

Done
Not sure. But eventually users will click restart, as usual.

[cryham]

Updated

[mgerhardy]

I think I remember again - this was here to ensure that the player doesn't just kill the npcs without transporting them. And if they killed enough npcs they are not able to win the match anymore. So either you are idling in the map without knowing what to do, or we have to find a way to tell the players that they have lost the match. So simply removing it might not be the best option here.

[cryham]

Well the old check was bad. Since it failed a map when all NPCs were in caves. I could easily trigger this.
So we should probably check how many NPCs were killed instead then.
I thought if we do it like now, users will simply restart a map eventually.

[cryham]

Rewrote it to count and fail map if killed all NPCs.