commands to do stuff with osc133 marked up output

With output between the OSC133 C (end of prompt, start of output) and D (end of output), do some useful things that mimic the things you can do with selections:

Add select-output to select the output of a command in copy-mode if the output is marked up with osc133. if collapsed, expand it first.

Add copy-output, copy-pipe-output, pipe-output to match the selection commands, but operate on current output rather than selection.

Add open-output which call spawn_editor() to open selection or current output in an editor. If there is an argument they should use that command (so "open-selection /usr/bin/vi"), if no argument they should use the editor option like spawn_editor() does by default.

current output = output under cursor, if no output, do nothing