Allow definition of routing table entries

Added a feature of adding route table entries, useful for example in this case:

server[10.0.0.1] <--> client[10.0.0.5] <--> client network[10.200.0.0/24] <--> workstation [10.200.0.50]

Basically, route option (10.200.0.0 255.255.255.0) is needed for openvpn server if one wants to have connection between 10.0.0.1 and 10.200.0.50.