Adds snake people (#2029)

Changes:
-adds snake people as a whitelisted species
-adds tail mechanics, ported from europa station, to the snake people, you can coil it up, people can attack it, stomp the tail and etc
-snake people can spit poison
-snake people can't use shoes
-snake people also have some other features like having a minor brute resist, claws and cuff breaking
-snake people can have different scale colors and eyes colors, but green is the best color without doubt
-also adds snake people

code/modules/mob/language/outsider.dm

@@ -130,4 +130,16 @@
 	space_chance = 10
 
 /datum/language/terminator/get_random_name()
-	return "HK [pick(list("Hera","Zeus","Artemis","Athena","Ares","Hades","Poseidon","Demeter","Apollo","Aphrodite","Hermes","Hestia","Dionysus","Persephone","Kronos","Odysseus","Ajax","Agamemnon","Chiron","Charon"))]-[rand(100, 999)]"
+	return "HK [pick(list("Hera","Zeus","Artemis","Athena","Ares","Hades","Poseidon","Demeter","Apollo","Aphrodite","Hermes","Hestia","Dionysus","Persephone","Kronos","Odysseus","Ajax","Agamemnon","Chiron","Charon"))]-[rand(100, 999)]"
+	
+/datum/language/snake
+	name = "Snake Language"
+	desc = "The tongue of the snake people, a lot of hissing."
+	speech_verb = "hisses"
+	ask_verb = "hisses"
+	exclaim_verb = "hisses"
+	colour = "vox"
+	key = "&"
+	flags = RESTRICTED
+	space_chance = 100
+	syllables = list("ssssss", "Hisss", "hSSSSS", "SSSSSSSSSSSSSS", "his!", "ssssSSSssss", "Sssssshshshshs", "S", "Hisss")