Rework hit type

[Linvail]

In the past, all buffs are limited to the caster itself. There was no "ranged buff" concept.
Since I added the ranged buffs capability, it is time to extend the hit types to include "own creature" or even "creature owned by allied players". They are used to ensure that the beneficial buff's SHOT will hit the hostile creatures.

This is not urgent because now all beneficial buff's SHOT object is beam-type, whose destination is set inside the target's body, making it won't hit any other creature (as long as the target is set properly).

Draft PR:
dkfans#3508