Fixes for slowdown and sensitivity in the demo

Firstly a big thanks to the fledgling community who have given us some great feedback. Although we still have some more to address, we thought it best to update as soon as we had fixes, particularly for the drastic framerate drops.

Fixed bugs:

• Framerate drop when enemies are stuck off the navmesh or it fails to load

• Mouse sensitivity is now halved (gamepad sensitivity is unchanged)

Upcoming planned fixes include adding FOV and quality settings to the options menu.

Known bugs:

• Enemies will sometimes not move, can be worked around by restarting the level

• An intended speed run route skips a checkpoint

• Restarting in the slaughterhouse may sometimes not give the player the speed mutagen, but the revolver with 6 bullets instead

• Physics can force the player out of the world

• Framerate can really suck in general

• Controllers can not operate the pause menu, only show or hide it

• Inventory screen doesn't work

• Objectives screen is nonsense

• Random opening door sound when starting the level

• Enemies turn around too slowly

• End section buzzsaws do not always kill the player

• More animation jank than you can shake a stick at