Packages for CentOS 8

I've now successfully built Dovecot packages for CentOS 8 that do not have the quota support stripped out. I was able to do this because CentOS has now finally shipped the quota-devel package as well as the other -devel packages that were previously missing from CentOS 8.

For those of you who are interested they are in the GhettoForge Testing repo for el8 at: http://mirror.ghettoforge.org/distributions/gf/el/8/testing/x86_64/

These are untested so let me know if anyone experiences any issues with them.

Peter