Addition of missing animal from alpha_mythology mod & minor anatomy corrections.

Apologies if i'm committing some kind of Major Faux pas here, I've been a long time out of the Community coding sphere and i'm trying to re-aquaint myself with all the tools. So i went looking for some low hanging fruit to try my hand at.

• Races_Animals.xml

• Added in missing alpha_mythology animal MM_StymphalianBird
• Moved MM_CeryneianHind from the bovine category into the cervine category as it is close to a deer then a cow.

• Hediffs_Earth_Animals.xml

• Updated 'dog anus' to display as 'canine anus' to better match other anus descriptions and improve use for creatures such as wolves, foxes and other canids.

• Alpha_Animals.xml

• Updated Alpha_Animals.xml to include male breast entries where appropriate so that they have nipples the same as other animals in the mod.