[Yum] upgrade and update

[seth vidal]

Hey all,
 I was doing some thinking about upgrade vs update and the confusion
around those two.

to clarify:
yum update - only updates packages you have installed does not include
or consult an obsoletes lists
yum upgrade - does updates + obsoletes

I was thinking maybe dump upgrade as an option entirely and include a
new option - like -o/--obsoletes to include the obsoletes lookup.

also have it matched with an obsoletes=1 in the config file.

That would remove one source of confusion and let people who want to use
obsoletes, always, just make a yum.conf modification and not modify
their yum.cron job.

-sv