Documented the three object collision routines

Test_Sprite_Collisions wasn't the only collision response. There was
also one for the Shield-projectile deflection, and there's one for the
Hyper forms' screen-nukes. These have been labelled, in order:
TouchResponse, ShieldTouchResponse and HyperAttackTouchResponse.

My understanding may be flawed, especially in the areas related to
collision_flags' highest two bits: HyperAttackTouchResponse has some
bizarre code relating to the bits being 11 that I can't make any sense
of. See HyperTouch_Special.
Improved Elemental Shield documentation

Ditched the idea of the '; +' labelling and just started using local
labels.
Added some more comments, added a missed equate and expanded upon the
meaning of some dbf values.