Somehow, these have always been right-associative, when the natural thing to expect is left-associativity. It now matters when trying to crawl down binary tree to display them properly.
Bumped into this randomly. We do correctly parse escape sequence, but
the format would simply but the unescaped string back on save. Now it
properly re-escapes strings before flushing them back. I also removed
the escape sequence for 'backspace' and 'new page' form feed as I
don't see any use case for those in an Aiken program really...
