Tweaks and fixes to the Chapter 1 maps. The following changes are:
-C1M1: Add line to block Imps near blue keycard. Adjust difficulty
settings on secret green armor and box of shotgun shells.
-C1M3: Minor difficulty tweaks. Fix tutti-frutti effect near the
end of the level.
-C1M4: Fix missing "SFALL" texture and tutti-frutti effects. Adjust
difficulty, primarily the amount of damage the toxic can do. 20% damage
toxic on the fourth level of the first chapter doesn't fit right.
-C1M6: Difficulty tweaks and edits to improve map flow. The way the
yellow keycard is retrieved has been changed in favor of a more
common "Open Door Stay (Fast)" action instead of the instant
floor raise trick to prevent confusion to less experienced players.
-C1M7: Difficulty tweaks. Fixed missing texture after grabbing red
keycard. Fixed tutti-frutti effect.
-C1M9: Implemented actual difficulty settings, as the map doesn't have
any. Added deathmatch spawns as this is the only map without any.
Added more items and other map edits.
-All: Rebuild nodes and blockmap with ZokumBSP
* removed a few crates outside
* reworked scenic vista in SW of map
* fixed all 1S lines to have the impassible flag
* fixed two stuck monsters at (-960, 1024)
* removed unneeded tag from sector 239
* removed a multi-patch mid-texture on a linedef
