Add DHCP server module for CVE-2014-6271
Merge branch 'review_3893' into test_land_3893
Add injection to HOSTNAME and URL
deregister options needed for exploitation
Refactor dhclient_bash_env to use the egypt's mixin mods
Fix Rex because domainname and domain_name were duplicated
Land #3893, @jlee-r7's exploit module for DHCP CVE-2014-2014-6271
Credit the original vuln discoverer