A smarter mergemaster

Folks,

I've got tired of dumb default choices mergemaster(8) offers
and modified it to be a bit smarter.  Upgrading /etc often,
as when following CURRENT, is much less pain to me now.  The
modified mergemaster is available from P4 for now since
I'd like to have it tested well before it hits the src tree.
The path is //depot/user/yar/hack/usr.sbin/mergemaster, also
accessible via web as
http://perforce.freebsd.org/depotTreeBrowser.cgi?FSPC=//depot/user/yar/hack/usr.sbin/mergemaster
Since mergemaster still is a shell script, you can just grab
and run it.  The manual page there has been updated as well.

The fruitiest features are as follows:

- mergemaster no longer teases you with pauses in -v mode.
  Use -N (novice mode) if you still want the pauses.
- "Stale" rc.d files can be rm'ed or kept on individual basis.
- There is expert mode, -E.  In this mode, mergemaster offers
  more dangerous defaults, mostly [install] or [delete] depending
  on the question.  So you can just keep hitting Enter most of the
  time if your /etc is just slightly modified.  In addition, you
  get the 's' choice when in a subdirectory: auto-install all files
  from this subdirectory -- much useful to deal with sweeping changes
  to rc.d or periodic.

Feedback is welcome.  And please please don't skip making a backup of
your /etc before running mergemaster!  I can't be responsible for its
loss due to bugs in my code or whatever.

-- 
Yar