Getting rid of passwd.conf.pre-sysinst

[Julio Merino <jmmv84%gmail.com@localhost>]

Hello,

As you probably know, if you choose to change the cipher algorithm for
system passwords from sysinst, sysinst generates a tiny passwd.conf
file and moves the original one out of the way.  This, in my eyes, has
two problems:

- It is inconsistent with how all other changes to files are handled.
In all other cases, we simply overwrite the distributed files with the
modified one.

- When upgrading the configuration files with etcupdate, it is hard to
understand the diff because the generated file is completely different
to the distributed one.  E.g. it lacks all header comments, uses a
different indentation...

I'd like to homogenize the situation by implementing in-place
replacement of the settings in passwd.conf with the algorithm chosen
by the user.  Actually I already have the code (modulo testing it =),
so I'm asking for comments about this change before I submit it.

Please CC me any replies.

Thanks,

-- 
Julio Merino