Saving endpoint DNS to config

[ntozaks]

If a DNS name is specified as an endpoint during configure, the DNS name gets stored in the configuration file. Name resolution occurs during serve.

Addresses issue #87

[Aptimex]

Initial test in the demo environment does not seem to be working, endpoint hostname is still getting resolved to an IP address immediately during configuration.

./wiretap configure -e wiretap-client-1:51820 -r 10.2.0.0/16
...
server command:
POSIX Shell:  ... WIRETAP_RELAY_PEER_ENDPOINT=10.1.0.2:51820 ...

cat wiretap_server.conf
[Relay.Interface]
PrivateKey = [...]
Port = 51820

[Relay.Peer]
PublicKey = [...]
Endpoint = 10.1.0.2:51820

[ntozaks]

The logic that I'm using to check for DNS doesn't account for numbers in the name. I will go back and fix that.

[Aptimex]

Seems to be working now with configure -e, but the server fails to start with an error when configure -o wiretap-server-1:51820 is used.