[PATCH] Projectile hit sound

[Mate-86]

Enhancement of the missile hit sound handling:

1. Allow the engine playing the sound using the position only (currently an entity is needed). A new cpp function should address that in SoundManager. This should fix the issue when the attacker dies before the projectile hits.
2. Introduce different kind of sounds in the template:
   1. the projectile hits the target or the ground (melee hit belongs here)
   2. the projectile starts causing the damage itself (eg. explodes) (useful when the damage is delayed, related ticket: #1911)

[elexis]

​Phab:D921

[fatherbushido]

In 20236:

Add a new function to emit a sound from a position not attached to an entity. Use it to improve the attack impact sound code and allow to emit that sound even if the attacker died meanwhile. Use the sound provided by Pureon for catapult. Fix #4779.

Patch By: Mate-86
Differential Revision: ​https://code.wildfiregames.com/D921