[CentOS] update to 7.4

Wed Sep 20 15:18:08 UTC 2017
Jerry Geis <jerry.geis at gmail.com>

Thanks all for the thoughts. I have no issues with 7.4 - this was clearly
"freek" accident while updating, either internet connection closed on me or
something. I brought the unit back here, I tried a few of the suggestions -
wasn't really working for me. So I just re-installed 7.4 and all was fine.

Thanks again.