feature proposal: vc-annotate for hg: include the author

[Uwe Brauer]

Hello

When I run vc-annotate in a file which is under git control the author
is shown. When I do the same for a file under hg control the author is
not shown.

However from the command line I can do

 hg annotate -u file.tex


And the author is displayed.

I don't see any variable which would allow me to make use of this
option.

Could that me added? Something like vc-annotate-backend-option or so.

Thanks

Uwe Brauer