Animal Fun - Birds

v1.7.17 -- Thank you Jessica and MarkCraft for staying up with me all night to fix these! Also thank you to everyone on my test server for all the rigorous testing; I appreciate it greatly!

• Added preen, rest and one-legged rest. The birds were greatly neglected on poses as one of my testers pointed out. These were started in a previous build but forgotten about until now.
• Added forage for ground feeding birds. Again, it was started and forgotten about.
• Adjusted the animation sequences to not go below ground (and looking dumb).