Upgrade to 1.0a via yum

[Michael Christy <christy jlab org>]

In the last week I have tried twice to install AC0.9 and upgrade to 1.0a
via yum.  After installing AC0.9, the yum update always seems to break
with what looks like inconsistent headers for the packages available.  Has
anyone else been able to do this recently, and if so could you walk me
through it?  AC1.0a looks very promising and I would really like to test
it out on my Alphas.

Eric