In system_checks/package_updates.py, we have a message for PACKAGE_NOT_UP_TO_DATE_MESSAGE.  That message has one long list of packages which isn't very helpful to the user when there are a lot of packages.  We need to reformat that somehow.

I think the minimum change we should do is to to alphabetize the list.

We can also add a remediation to this which says the user could run yum update}} to update all the packages on the system.