Add '%' operation (accidentally omitted)
Add strMode function to properly handle String mode (broken before)
Change null checks to use null say let
Add peek function to handle peeking an empty stack (returns 0)
Fix '\' operation (broken, did not swap top 2 stack elements)
Add temporary output handling for testing
Add temporary input handling for testing
Add '0' - '9' operations (unintentionally omitted before)
Fix skipping spaces while in String mode
Step returns whether pointer is inactive or not; whether the program has terminated
