Quick Start Guide updated for RHEL rpms, and CLI syntax

Quick Start Guide updated for RHEL rpms, and CLI syntax

The names of the RHEL rpms have been updated to reflect what is
actually published on openafs.org, and the CLI syntax of the commands
run using -noauth have had the unnecessary -cell options removed.

Change-Id: I5c03d371c822d1d064660a3b00fb3d1e64bff141
Reviewed-on: http://gerrit.openafs.org/2914
Reviewed-by: Russ Allbery <rra@stanford.edu>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>