COPR chroots additions/deletions

[Michal Novotny]

Hello,

I have added the following chroots

custom-1-i386
custom-1-ppc64le
custom-1-x86_64
epel-7-i386

and removed

fedora-rawhide-i386
fedora-rawhide-x86_64
.

Custom chroots were a long expected feature that enable you to configure
your build environment almost at free will (by additional repos per chroot
and additional buildroot packages).

epel-7-i386 chroot was requested in *Bug 1271977*
<https://bugzilla.redhat.com/show_bug.cgi?id=1271977> - RFE - asking for
el7 i386 build option. It was somehow missed when epel-7 chroots were added
so finally we have it.

fedora-rawhide chroots were some residue of the yesterday's release. They
should have been already disabled as fedora-26 chroots replaced them.

clime