v1a - optimization fixes n stuff

- Removed all grass sprites for performance (rip)

- Added ladder towards the rooftop of the lab for human and zombie mobility

- Closed up a ton of translucent windows in the surface section so sigil spots arent rendering the outside area of the
map (basically turning it into a secluded room)

- Clustered up a lot of trees together for performance, they're one single model now vs 6-7 individual ones.

- Added extra hints and occluders and more aggressive prop fade on some props.

- Brightened up some parts of the map a bit for more visual clarity

- Removed some unused assets, however the map is no longer repacked, map size from 130 > 215 but freezes are
fixed

- Opened up the maintenance building's back so zombies can just waltz into the alternate entrance to the sewers
instead of having to possibly have to break down a barricade

- Some extra props here and there

Initial addon creation.