change hostname in RHEL (CENTOS) 7

# hostnamectl
# hostnamectl set-hostname newHostname

Thanks to:
http://webplay.pro/linux/change-hostname-permanently-centos-7.html
http://www.server-world.info/en/note?os=CentOS_7&p=hostname
http://ask.xmodulo.com/change-hostname-centos-rhel-7.html