Makes the `isorgan()` define more sane

[DGamerL]

What Does This PR Do

Changes the isorgan() define to is_external_organ() Changes the is_int_organ() proc to a define is_internal_organ() Adds 1 new define: is_organ()

Why It's Good For The Game

I just spend 10 minutes debugging why isorgan() wouldn't say a fleshy mass was an organ, it's not an intuitive name.

Testing

It compiled, and I checked the diff twice

Changelog

NPFC