Bug with linedef special 40 and Doom 1

[printz]

In Eternity Doom 1, linedef type 40 (raise ceiling to highest neighbouring ceiling) lowers the floor as well. This is a bug, as it doesn't happen in DOOM.EXE. It also (correctly) does not happen in Eternity Doom 2; I only got it to happen in Doom 1.

Demonstration wad: Ceiltest.wad, Doom 1 E1M1 (but compatible with Doom 2, so you can compare).

[Quasar]

Bump to note fixed as of r2287

[Csonicgo]

I'll add these changes to the MinGW compile tonight.