Throw impacts play the thrown object's hitsound
Items now have a throwhitsound var

If throwhitsound isn't defined, a thrown item calls the hitsound
instead. If that isn't defined, no sound is played.

Circular saw now calls pierce.ogg as its throwhitsound instead of its
hitsound.
Item throwtapsound var for forceless objects
Merge pull request #2482 from Tenebrosity/throwsounds

Thrown objects play throwhitsound