Add flags to enable QUIC agent.

QUIC agent was restored as an experimental feature in an earlier change.
To enable QUIC agent, please build and pack conference server with
following commands:

./scripts/build.js -t quic -t <mcu or other target>
./scripts/pack.js -t all -t quic-agent -p <sample web app path>

Author: jianjunz

scripts/pack.js

@@ -19,7 +19,7 @@ optParser.addOption('r', 'repack', 'boolean', 'Whether clean dist before pack (E
 optParser.addOption('e', 'encrypt', 'boolean', 'Whether encrypt during pack (Eg. pack.js -t portal -e)');
 optParser.addOption('d', 'debug', 'boolean', '(Disabled)');
 optParser.addOption('o', 'addon-debug', 'boolean', 'Whether pack debug addon (Eg. pack.js -t webrtc-agent -o)');
-optParser.addOption('f', 'full', 'boolean', 'Whether perform a full pack (--full is the equalivation of pack.js -t all -r -i)');
+optParser.addOption('f', 'full', 'boolean', 'Whether perform a full pack (--full is the equalivation of pack.js -t all -r -i). Experimental features are not included, please include them explicitly with -t.');
 optParser.addOption('p', 'app-path', 'string', 'Specify app path (Eg. pack.js -t all --app-path ${appPath})');
 optParser.addOption('a', 'archive', 'string', 'Specify archive name (Eg. pack.js -t all -a ${archiveName})');
 optParser.addOption('n', 'node-module-path', 'string', 'Specify shared-node-module directory');
@@ -45,7 +45,10 @@ const experimentalTargets = ['quic-agent'];
 var allTargets = [];
 
 if (options.full) {
-  options.target = ['all'];
+  if (!options.target) {
+    options.target = [];
+  }
+  options.target.push('all');
   options.repack = true;
   options['install-module'] = true;
 }
@@ -119,7 +122,11 @@ function getPackList(targets) {
     console.log('Avalible Targets Are:');
     console.log('---------------------');
     for (const target of targets) {
-      console.log(`\x1b[32m${target.rules.name}\x1b[0m`);
+      let targetTitle = `\x1b[32m${target.rules.name}\x1b[0m`;
+      if (experimentalTargets.includes(target.rules.name)) {
+        targetTitle += ' (experimental feature)'
+      }
+      console.log(targetTitle);
       console.log(' ->', target.path);
     }
     process.exit(0);
@@ -130,7 +137,7 @@ function getPackList(targets) {
   }
 
   var packList = targets.filter((element) => {
-    // Don't include QUIC agent by default until CI is added for QUIC SDK.
+    // Experimental features are not included by default.
     if (options.target.includes('all') && !experimentalTargets.includes(element.rules.name)) return true;
     return options.target.includes(element.rules.name);
   });
@@ -592,7 +599,7 @@ function packScripts() {
   }
   scriptItems.push('app');
   scriptItems.forEach((m) => {
-    if (experimentalTargets.includes(m)) {
+    if (!options.target.includes(m) && experimentalTargets.includes(m)) {
       return;
     }
     startCommands += '${bin}/daemon.sh start ' + m + ' $1\n';