Fix formspec escaping, add escaping to info.txt for texture packs.

builtin/misc.lua

@@ -99,10 +99,3 @@ function minetest.setting_get_pos(name)
 	return minetest.string_to_pos(value)
 end
 
-function minetest.formspec_escape(str)
-	str = string.gsub(str, "\\", "\\\\")
-	str = string.gsub(str, "%[", "\\[")
-	str = string.gsub(str, "%]", "\\]")
-	return str
-end
-