BREAKING: Interface name is now specified by configuration file

The syntax for the hypd server command has changed.  Now instead of specifying an interface name as an argument to the server command, you instead specify a configuration file path.

Example:
./hypd server hypdconfig.json

hypd/cmd/defaultconfig.go

@@ -16,7 +16,9 @@ var defaultconfigCmd = &cobra.Command{
 	Use:   "defaultconfig",
 	Short: "Prints the default configuration to stdout",
 	Long: `The default configuration is used if one is not set.  The default configuration
-	can be used as a reference to build your own.  `,
+can be used as a reference to build your own. 
+
+hypd generate defaultconfig | tee hypdconfig.json`,
 	Run: func(cmd *cobra.Command, args []string) {
 		config := configuration.DefaultConfig()
 		b, err := json.MarshalIndent(config, "", "    ")