XDF Compatibility: proper support of q3 haste
Current state: item_haste is replaced by buffs (which means RANDOM buff from the ones enabled on the server), which can be picked up by players. target_give entities don't work for item_haste. target_init works properly (removes the buff if spawnflags demand it).
- verify that xonotic speed buff adjusts the very same movement params as q3 haste does (if needed make a cvar to switch between xonotic/q3-compat speed mode) (packer mimics q3 haste by setting sv_maxspeed and sv_maxairspeed to 400 (which is a mistake cause should be 416))
countfield of the
item_hasteentity which sets how many seconds should the haste/speed last.
- Fix the spawnpoint and non-spawnpoint triggers to support giving haste.