Player_api: Various maintenance (#2737)

Clear 'player_sneak' and 'player_api.player_attached' table values
when player leaves.
Remove unnecessary commas and whitespace.
Fix table name in 'game_api.txt'.
Clean up documentation in 'game_api.txt'.

mods/player_api/api.lua

@@ -68,7 +68,7 @@ function player_api.set_textures(player, textures)
 	local model = models[player_model[name]]
 	local model_textures = model and model.textures or nil
 	player_textures[name] = textures or model_textures
-	player:set_properties({textures = textures or model_textures,})
+	player:set_properties({textures = textures or model_textures})
 end
 
 function player_api.set_animation(player, anim_name, speed)
@@ -90,6 +90,8 @@ minetest.register_on_leaveplayer(function(player)
 	player_model[name] = nil
 	player_anim[name] = nil
 	player_textures[name] = nil
+	player_sneak[name] = nil
+	player_api.player_attached[name] = nil
 end)
 
 -- Localize for better performance.

mods/player_api/init.lua

@@ -5,7 +5,7 @@ dofile(minetest.get_modpath("player_api") .. "/api.lua")
 -- Default player appearance
 player_api.register_model("character.b3d", {
 	animation_speed = 30,
-	textures = {"character.png", },
+	textures = {"character.png"},
 	animations = {
 		-- Standard animations.
 		stand     = {x = 0,   y = 79},