New features:
[webgui] new web GUI with new Angular technology v12
[ssl] letsencrypt integration
[lslb] http: add and delete HTTP headers
[lslb] http: priority load balancing support
[lslb] http: rewrite URL directive (proxy pass)
[lslb] http: updated Relianoid HTTP/S core zproxy
[lslb] l4: updated Relianoid L4 core nftlb
[zcli] Relianoid command line improvements
[api] 4.0.2 API version