Bug#438560: [vim-common] vim -C isn't 'compatible'

[Matt Wozniski]

Only one comment on this - the man page/vim help are misleading, but
not wrong.  Removing "set nocp" from the default vim setup is probably
not the way to go either, by the principal of least surprise... But,
to get vim to start vi-compatibly in spite of the startup files, you
can do this: vim --noplugin -c "set nocp cpo&vi"