many changes from testing

lib/utils/select-sbc.js

@@ -0,0 +1,13 @@
+const CIDRMatcher = require('cidr-matcher');
+const matcher = new CIDRMatcher([process.env.JAMBONES_NETWORK_CIDR]);
+
+module.exports = (sbcList) => {
+  const obj = sbcList
+    .split(',')
+    .map((str) => {
+      const arr = /^(.*)\/(.*):(\d+)$/.exec(str);
+      return {protocol: arr[1], host: arr[2], port: arr[3]};
+    })
+    .find((obj) => 'udp' == obj.protocol && matcher.contains(obj.host));
+  if (obj) return `${obj.host}:${obj.port}`;
+};