lei rediff: add --dequote and --requote?

lei rediff: add --dequote and --requote?

[Eric Wong]

I find "lei rediff" useful when writing replies to patch emails.
Like any good *nix tool, my $EDITOR allows piping either the
full or partial editor buffer into arbitrary commands.

Besides typing text, the most important feature of my editor is
the ability to run/pipe-to arbitrary commands (e.g. git-am, lei
blob, git-show); and "lei rediff" is a new one.

I barely customize my editor; however, I do have some editor
macros for quickly stripping and adding quote prefixes (at least
the standard "> " mail quoting style, along with '#' for sh/Perl).

But maybe others do not have these macros, so I wonder if
"rediff" should support --dequote and --requote switches to ease
this usage pattern.

Or/and if "lei dequote" and "lei quote" should exist as
(slower) replacements for `sed 's/^[> ]\+//'` and `sed 's/^/> /'`,
respectively.