string.Split and string.SafePattern

[vugi99]

It's annoying to copy the same code over and over to split strings. (Plus some of my versions in my packages had bugs or limitations)

-- Makes a safe string to append in a pattern without triggering special lua pattern rules
function string.SafePattern(str)

--[[
Splits strings, using a simple delimiter or a pattern delimiter
]]--
function string.Split(str, delimiter, is_pattern)