[Secure-testing-team] Bug#763012: bash: 'dpkg --purge bash' should work, rather than give this:

[Troy Benjegerdes]

Package: bash
Version: 4.2+dfsg-0.1+deb7u3
Severity: critical
Tags: security
Justification: breaks the whole system

Dear Maintainer,
Please consider allowing the following to work in (some) situations:
# dpkg --purge bash
dpkg: error processing bash (--purge):
 This is an essential package - it should not be removed.
Errors were encountered while processing:
 bash


-- System Information:
Debian Release: 7.6
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.17.0-rc1+ (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages bash depends on:
ii  base-files   7.1wheezy6
ii  dash         0.5.7-3
ii  debianutils  4.3.2
ii  libc6        2.13-38+deb7u4
ii  libtinfo5    5.9-10

Versions of packages bash recommends:
ii  bash-completion  1:2.0-1

Versions of packages bash suggests:
pn  bash-doc  <none>

-- no debconf information