cherry pic from 'hotfix/3347-Certificate_Authority_SAN_names_not_working':

bugfix #3347: Certificate Authority SAN names not working in 2.1

subjectAltName can be set _only_ via configuration file - created three extra sections in openssl.cnf to use in case of existing subjectAltName.

Unfortunately it is not possible to assign empty value to subjectAltName in openssl.cnf
Merge pull request #1258 from yarick123/master
Do not reconfigure dhcpd twice on secondary after config sync. Fixes #3797
Hide FreeBSD version from sshd banner. It fixes #3840
Fix comment in css
Replace GET by POST, it fixes #3833