Fixed cats crashing after latest gmod update.

Fixed navmesh error showing regardless if there was a navmesh. Added experimental networking (npc_siamesecat_experimentalnw 0) to disable.

Adding ability to turn off the missing navmesh warning.
npc_siamesecat_disablenavwarning 1

Added a new animation, and they sort of chase birds and kill them now. They should get stuck less as well. Also did some minor optimizations and made it so the sounds aren't super loud.

Version 0.3C[/b]
- Should have fixed most issues with the animations.
- Removed the debug messages I accidently left inside.
- Cats will now blink!

Made some minor changes I accidentily left out.

Version 0.3B
- Issues where the cat would stop following you should be fixed. Keep in mind they should stop following you when you die, disconnect or shoot them, which is intended.
Some notes about following, they will prioritize eating, drinking, and sleeping before following you, but afterwards they should start following you again. If for some reason they don't, they should start following you again briefly after idling.
- Any problems with the cat not going to find food or water should be fixed, although if there aren't any spawned they will act as they originally do.
- Some other smaller bug fixes that I can't recall, I need to keep better track of these.
- Added three new skins! The cats now have ten different skins!

Version 0.3A
- There are now two new stats for the cat, hydration and fatigue. You may give the cat water by spawning the water bowl entity, and when the cat is thirsty enough it will go to it. If you do not keep your cat hydrated, it will take damage until it dies. Fatigue isn't really harmful, although it will make your cat sleep a lot.
- The HUD has been redesigned, once again you can view it by holding left shift while hovering over a cat, cat food, or a water bowl.
- Added another collar.
- Some other small fixes.

Version 0.2B:
- New collision model, should work better than the last one, and the hitboxes are much better. Although it's not perfect and is a work in process. Let me know of any issues with it.
- Cats will now randomly spawn with a bowtie, flower, or nothing on their head. I'd like to add more accessories for the cats, so if you have any reasonable ideas please post them in the suggestions.
- Fixed an issue where other players could stop your cat from following you.

Version 0.2A:
A decent amount of changes were made, it is very likely there will be some bugs.

- Added sleeping, will happen randomly.
- Added aging, the cat grows as it ages.
- Added hunger, you must now feed the cat, spawn a Catfood entity, which was just added, and when your cat is hungry enough it will go after it. ( This still needs some work )
- Particles will now frequently be emitted from the cat depending on it's mood or actions taken agaisnt it.
( Users may disable particles with npc_siamesecat_enableparticles 0 )
- A HUD was added for the cat, hover over it and hold left shift. You may also see how much food is left in a bowl the same way. The HUD is just temporary, I plan to redo it.
- Two new skins, and when you press E on a cat to follow you, it is given a collar.
- Ability to get a cat unstuck, doesn't always work, but you go up to it and hold R and then press E. It should jump.
- Some other changes I can't remember

If you don't feed your cat it will die, it can also die of old age.
You may completely disable dying, even by bullet with this ConVar.
npc_siamesecat_enabledeath 0

Here are some other ConVars..
npc_siamesecat_soundvolume - Value should be 0 - 100. Default: 100
npc_siamesecat_hungerrate - How many seconds are inbetween each hunger tick. Default: 120
npc_siamesecat_maxage - The cat's maximum age, the larger the age, the bigger the cat grows. Default: 5
npc_siamesecat_agerate - How many seconds are inbetween each age tick. Default: 120