experimental conffile merge for dpkg

[Jarno Elonen <elonen@iki.fi>]

Hi,

I've written an experimental conffile merge support for dpkg.

http://elonen.iki.fi/code/dpkg-merge/ contains the patched dpkg
and a new interactive python & curses based two-way merge tool
called imediff2 (+ 3 screenshots for the impatient).

For those who would like try it:

  + install 'dpkg_1.10.10merge_i386.deb'
  + install 'imediff2_1.0-1_all.deb'
  + run 'export MERGE2=/usr/bin/imediff2'
  + install some package with updated conffiles
    and press 'm' (the option is only visible if
    the MERGE2 environment variable is set)

The changes to dpkg are also in a separate patch file,
'dpkg-merge.patch'

Here's the proposed changelog for dpkg:

   * Added an experimental 'Merge' option
     (Closes: #189805, #48717, #120152)
   * Enclosed file names with quotes in command string (Closes #147583)
   * Added a message with the path of the new conffile in Suspend
   * Ignore SIGINT while waiting for child processes so that dpkg
     doesn't die if the child is ctrl-c'd

- Jarno