Integration of k5start/krenew functionality

[ghudson@MIT.EDU]

At the request of an OS vendor, we are looking into adding the
functionality of k5start and krenew for the 1.8 release.  I've written
up an early project proposal at:

  http://k5wiki.kerberos.org/wiki/Projects/Process_Credential_Management

I'm interested in feedback particularly on the interface design
options.  I do not yet have strong opinions about what the interface
should look like, and am willing to spent a little extra time to get
it "right" as opposed to just taking an easy option.
http://www.eyrie.org/~eagle/software/kstart/ has links to the man
pages for k5start and krenew, which may be instructive background.

I'm also interested in any concerns Russ or packagers of the kstart
code might have about the way we do this.