B7 and B7a (#6)

B7:
- Broke up a large singular func_detail entity to allow it to unload normally, and segmented it so that areaportals would unload it properly as well.
- Separated timer entities into their own visgroup.
- Broke up bits of the log cabin to avoid a series of triangulation errors.
- Visleaf optimization which required a new shape being given to the fountain's water, rebuilding the spawn room's cafeteria seating lights, and rebuilding the skylights in the unusual viewing area. Additional Hint brushes have been added to simplify cut leaves.
- Sealed the boxing ring enclosure and fixed a triangulation error.
- Fixed an improper origin of a func_door that leaked to the void.
- Added a briefing picture.

B7a:
- Took visgrouped timer entities and removed them from the compile. Roaring Rockets, Mega Strike, and Show Stopper do not repeatedly emit, but having a timer stop and start all of the effects causes a memory leak. Spectral Swirl, Infernal Smoke, Infernal Flames, Spooky Night, and Ominous Night all do not clean up properly when sent a stop command and should not be sent that command. They have been renamed with a _nostop appended. Rotating effects will eventually break orbit without restarting the entities.
- Consolidated the two logic_auto entities into a single entity. Added lines to make it initiate the new _nostop particle emitters as well.

trade_ngs_day/materials/vgui/maps/menu_photos_trade_ngs_day_b7a.vmt

@@ -0,0 +1,7 @@
+"UnlitGeneric"
+{
+ "$basetexture" "vgui\maps\menu_photos_trade_ngs_day_b7a"
+ "$translucent" 1
+ "$ignorez" 1
+ "$vertexcolor" 1
+}