Merge branch 'jc/whitespace-incomplete-line' into next

Merge branch 'jc/whitespace-incomplete-line' into next

Both "git apply" and "git diff" learn a new whitespace error class,
"incomplete-line".

* jc/whitespace-incomplete-line:
  attr: enable incomplete-line whitespace error for this project
  diff: highlight and error out on incomplete lines
  apply: check and fix incomplete lines
  whitespace: allocate a few more bits and define WS_INCOMPLETE_LINE
  apply: revamp the parsing of incomplete lines
  diff: update the way rewrite diff handles incomplete lines
  diff: call emit_callback ecbdata everywhere
  diff: refactor output of incomplete line
  diff: keep track of the type of the last line seen
  diff: correct suppress_blank_empty hack
  diff: emit_line_ws_markup() if/else style fix
  whitespace: correct bit assignment comments