Allow defining a SRVIPNETMASK that will be used in all applicable configurations including the previously omitted ifconfig tap_soft in build/services.d/softether-vpnsrv/run script. This addresses issue #9
Updated 10-routing.sh to set the CIDR subnet using a function to convert the supplied xx.xx.xx.xx netmask.
Updated 20-dhcp-conf.sh to additionally replace SRVIPNETMASK defaulting to 255.255.255.0 which was the original default hard coded value.
Updated README.md and init-env.sh to specify the added SRVIPNETMASK value.
fix for issue #9
ifconfig tap_soft
inbuild/services.d/softether-vpnsrv/run
script. This addresses issue #9