Update comment
Remove the timeout if the buffer changes
Fix lazily adding the diff renderer
Fix unicode warning when diffing
Fix diffing a new file in a git repo
Be explicit about what the bounds are
Fix getting the last line of text

Also only get the visible text.
Add a bit of xpadding to the diff renderer

Otherwise it is simply too close to the text
and burns my eyes.
Take file length into account when delaying the diff

Otherwise large files delay for an unacceptable
amount of time.