Bug#703901: debian-installer: GRUB should allow detailed configure for MD RAID

[Mason Loring Bliss <mason@blisses.org>]

Package: debian-installer
Version: Wheezy RC1 AMD64
Severity: normal
Tags: d-i

Dear Maintainer,

When I install a software RAID 1 system, there is no option, even with an
expert install, to install GRUB to multiple MBRs. I have return after the
install and dpkg-reconfigure grub-pc, where selecting multiple devices as
targets during the install would seem more sensible and less prone to being
forgotten. (If the option exists and I'm just missing it, it's well-hidden!)

-- System Information:
Debian Release: 7.0
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.2.0-4-amd64 (SMP w/3 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash