Fixed fqdn handling on debian/ubuntu

The issue was that the old method simply didn't work.  When the hosts
file should look like:
    127.0.1.1   host.fqdn.com host
It looked like:
    127.0.1.1   host.fqdn.com host old.fqdn.com old
Or this if the user didn't set a fqdn
    127.0.1.1   host host old.fqdn.com old

This patch fixes that.
Allow to change the DHCP_HOSTNAME on RedHat
Merge pull request #2267 from fcharlier/fcharlier/dhcp_hostname_redhat

guests/redhat: Allow to change the DHCP_HOSTNAME on RedHat
Update CHANGELOG
Merge pull request #2254 from Caustic/fix-hostname-debian

guests/debian,ubuntu: Fixed fqdn handling
Update CHANGELOG
website/docs: mention installing virtualbox
add cfengine provisioner suse install support
Resolving #2194 (Ansible buffering output if run as subprocess)
fixed a broken link
Merge pull request #2284 from jeremyquinton/link_fix

website/docs: fixed a broken link
Remove old /tmp/bootstrap_salt.sh before uploading as it may not be writeable
Merge pull request #2290 from ianheggie/fix_provision_permissions_error_on_bootstrap

provisioners/salt: remove bootstrap definition on each run
Update CHANGELOG
core: Translation to remove 'solo' from shared chef error [GH-2276]
Merge pull request #2273 from czi/fix/master/my_contribution

guests/suse: Update CFEngine provisioners plugin for SuSE install compatibility
Update CHANGELOG
website/docs: Document remote shell provisioner
provisioners/chef: use real variable in delete from chef sever [GH-2300]
Merge pull request #2301 from fgrehm/document-remote-shell-provisioner

website/docs: document remote shell provisioner