Please backport coop shoot through allies zadmflags from upstream Zandronum

[Alexander230]

Zandronum 3.1 has zadmflags 2097152 (sv_ShootThroughAllies) and 4194304 (sv_DontPushAllies), which are great quality of life features for coop games. Please port them to Q-Zandronum.

[IgeNiaI]

I am approaching the release of QC:DE 3.0 and would like to do as little changes on all components as possible. This change is fairly complicated and involves a bunch of new actor flags. So I won't do it for now. I might do it after QC:DE 3.0 is out, but your best bet is to wait until Zandronum and Q-Zandronum get merged.

[Alexander230]

Ok, thank you!