[Warps & Doors] Issue with warp numbering.

[Alucard648]

1. Create New level.
2. Add one warp pair. It will receive index number 1.
3. Add another warp pair. It will receive index number 2.
4. Delete warp pair #1 via "minus" button in Warp Propeties box.
5. Add another warp pair.

Result: instead of getting ID#1, newly added warp pair will receive ID#3, which will render warp slot#1 unused until deletion from step 3 is undone via "Undo" command. It`s not fun having to search a level that warps to this level via unused warp ID in an episode with 150 levels linked together after accidental press of "minus button" and subsequent editor crash (in any way) to reassign warp point to newly used one.

[Wohlstand]

That because I don't recounting a warp ID's after deletion form begin/middle. This may slow performance and increase memory usage to record history, undo/redo this requires reverse recounting to "restore" deleted warp entry. Anyway it's possible to don't overflow memory: have a short commands to recount warps in range (at place where deleted/inserted warp to end).