Be smarter about cleaning the staging area.

Be smarter about cleaning the staging area.
Clean output area if packaging.  (Will not clean if -nopackage specified.)

Pull corebinaries from staging area instead of from target area.

Don't sign before making zips.  Build products are only signed in the staging area before any packaging is done.  (Packaging products are signed when copied to the output area.)

Previous change: Add relnotes.html to output area.

Target_Version: 1.6.1
Ticket: 5490
Tags: pullup

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@19371 dc483132-0cff-0310-8789-dd5450dbe970