Improved group spawning

[SkaceKamen]

• add new option (on by default) to reuse existing groups when spawning
  • without the second option, this could cause some AI issues, mainly the rest of the group always waiting for the spawned unit to get to them
• add new option (on by default ?) to spawn units close to group units when possible (no enemy nearby)
  • this can cause some obvious visible spawns, but on the other hand it resolve obvious spawn locations
  • should be balanced so defenders spawn more in the back and attackers should always pick whatever is closer (sometimes the picked spawn can be further from objective than normal spawn)

This current implementation of the group spawn is very simple and doesn't account for pretty much anything. As noted it should be improved before it's ready to be used.

[Cam0m1le]

Hello! When can we expect the release of these options? I really look forward to them.