Only launch dhcpcd for ethernet interfaces
[configs/releng] Add clonezilla/drbl to live-enviroment

Signed-off-by: Gerardo Exequiel Pozzi <vmlinuz386@yahoo.com.ar>
Merge remote-tracking branch 'upstream/master'
Split README into several files. Update scripts

Added 'set -e -u' to scripts and fixed bugs in build-custom.sh.

Moved README.md to archiso.git directory and moved main sections
out into separate files in custom/notes/