WIP attempting to track output locations

[camertron]

Hey @mbj :) This is the approach I came up with for emitting output locations. I made only a small number of the necessary changes. I'd like to ask for your feedback before making any further progress. What do you think? Here's a quick usage example:

# NOTE: the buffer parameter here can be removed eventually, I added it for debugging purposes
Unparser.unparse(ast) do |buffer, old_pos, new_pos|
  ...
end

[mbj]

@camertron I'm tooooo busys to reply verbosely. Your approach is right, but. and that but requires a longer elaboration I cannot find the time for this and likely next week.

[camertron]

@mbj hahaha no problem, no rush!