[CentOS] Manual partitioning and LVM

[Kenneth Porter]

I was able to assign the resulting partitions within the installer. I did 
have to check "reformat" on all the ext4 partitions to make it happy.

It's now loading packages. It does throw up an error early that the 
authselect package is missing. I've never seen that package name before. 
I'm using this mirror and there's no RPM of that package in the Packages 
directory:

<http://mirrors.ocf.berkeley.edu/centos/7.7.1908/os/x86_64>