enables tail, horns, ears bodyparts for ipcs; changes ipc hair to opaque

[cyfause]

About The Pull Request

Changes the mutant_bodyparts list in ipc.dm to include "mam_tail", "mam_ears", "horns" (enables tails, ears, horns);
Modifies hair_alpha on ipc.dm to be set to 255 (full opacity) in order to fix body parts becoming translucent (for some reason).

Why It's Good For The Game

Having extra options for a species = good, in my opinion. The only downside, hair now becomes full opacity on IPCs.
I understand if PR gets closed for this reason, I have not been able to find the tie between hair_alpha and body parts (yet) so this is the best I can do. Ideally, hair opacity would be kept the same, while body parts are kept opaque.
Still, I believe the benefit of having extra selectable body parts outweighs the negligible downside of losing hair translucency (previous value 210).

A Port?

Not a port.

Pre-Merge Checklist

• You tested this on a local server.
• This code did not runtime during testing.
• You documented all of your changes.

Changelog

🆑
tweak: enables tail + horns + ears bodyparts for ipc characters
tweak: disables opacity on ipc character hair
/:cl: