grep: display correct user/revision for --all in reverse.
Also handle multiple occurrences of the same line by storing
linestates in an array instead of a dict, and using difflib
to compute the difference between linestates.
(the addremove command is deprecated; use add and remove --after instead)
adding dir/bar
adding foo
dir/bar
foo
(the addremove command is deprecated; use add and remove --after instead)
adding dir/bar_2
adding foo_2
dir/bar_2
foo_2