This set of changes adjusts the script so that you can run it multiple times with the same input and not have any unexpected changes. This makes it appropriate for "enforcing state", as required by automated provisioners like Puppet, Salt, Chef, or Ansible.
- Unbound, OpenVPN, easy-rsa, and other dependencies are only installed from upstream if they are not already present. This prevents multiple runs of the script from causing unexpected version upgrades.
- The easy-rsa system is put in a folder called "easy-rsa-auto" so it can't conflict with the "easy-rsa" folder from some older OpenVPN packages
- The easy-rsa CA is only initialized once
- SERVER_CN and SERVER_NAME are randomly generated once and saved for future reference
- File append ('>>') is only done strictly after a file is created with '>' (e.g. /etc/sysctl.d/20-openvpn.conf)
- Clients are only added to easy-rsa once
- If AUTO_INSTALL == y, then the script operates in install mode and doesn't enter manageMenu
