GEOMETRY_CMDTITLE has issues with escape codes

[Tor Arne Vestbø]

E.g.:

printf '\e]8;;http://example.com\e\\This is a link\e]8;;\e\\\n'

Will results in corrupted output.

[Duncan Beevers]

Hey @torarnv I'd love some help making the escape functionality more robust. I wrote it with limited experience and testing with just a few "normal" titles.

#302