(hopefully) fixed CreateConVar errors and added IsValid() checks for the player's active weapon.

-Fixed an issue with the Gravity Gun not distinguishing between punts and attracts, meaning it would instantly launch any prop that was picked up
-Re-enabled WASD movement - mind this movement is relative to your aiming angle and not your view angle - suggested by stone cold steve austin
-Made the gmarcade_fade command off by default (it and the other commands are now under FCVAR_ARCHIVE, meaning they stay consistent between map loads)

Added convar gmarcade_fade that adds a fade to black while on the move.

Added reload compatibility. Fixed automatic flashlight not turning off when gmarcade_enabled is set to 0. Adjusted crouch sensitivity to be higher.

Hopefully fixed issues with stairs in d1_canals_01. Also added prop_dynamic to the Move Mode list, so your player shouldn't want to shoot trains anymore.