lclplant a6

• The stage now connects to stage 2/chemplant correctly and without seams (but chem is still visgrouped out)
• Simplified B and added a high ground route for attackers and defenders to consider. It might be too powerful.
• Simplification entails: fewer entrances/exits to B's ring, better lighting from sky light (it's open air now), fewer weird dev materials in odd places, and cleaned up brushwork.
• A completely new connector is now present in the tunnels between A and B. The map should be more balanced as a result, but it's not very architecturally interesting and it may need spawn times to be adjusted to match it.

I've also added a new route to A's upper ground to attackers on the far left. It may not play well; I was just experimenting.