Use UTC time format in onos-lib-gen

Also remove an extra space

Change-Id: Ia5a7636189be0cb5e961133f504c1d92c7a4445e
diff --git a/lib/BUCK b/lib/BUCK
index f97b618..6268695 100644
--- a/lib/BUCK
+++ b/lib/BUCK
@@ -1,7 +1,7 @@
-# ***** This file was auto-generated at Fri Feb 17 08:57:18 PST 2017. Do not edit this file manually. *****
+# ***** This file was auto-generated at Sat, 18 Feb 2017 00:45:58 GMT. Do not edit this file manually. *****
 # ***** Use onos-lib-gen *****
 
-pass_thru_pom( 
+pass_thru_pom(
     name = 'onos-dependencies-pom',
     src = 'pom.xml',
     out = 'onos-dependencies.pom',
diff --git a/tools/build/libgen/src/main/java/org/onosproject/libgen/BuckLibGenerator.java b/tools/build/libgen/src/main/java/org/onosproject/libgen/BuckLibGenerator.java
index f05593d..563e55b 100644
--- a/tools/build/libgen/src/main/java/org/onosproject/libgen/BuckLibGenerator.java
+++ b/tools/build/libgen/src/main/java/org/onosproject/libgen/BuckLibGenerator.java
@@ -30,9 +30,10 @@
 import java.net.URLConnection;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.format.DateTimeFormatter;
 import java.util.ArrayList;
-import java.util.Date;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -166,6 +167,7 @@
     }
 
     void write(String outputFilePath) {
+        DateTimeFormatter formatter = DateTimeFormatter.RFC_1123_DATE_TIME.withZone(ZoneId.of("UTC"));
         File outputFile = new File(outputFilePath);
         if (!outputFile.setWritable(true)) {
             error("Failed to make %s to writeable.", outputFilePath);
@@ -173,11 +175,11 @@
         try (PrintWriter writer = new PrintWriter(outputFile)) {
             writer.write(String.format(
                     "# ***** This file was auto-generated at %s. Do not edit this file manually. *****\n",
-                    new Date().toString()));
+                    formatter.format(Instant.now())));
             writer.write("# ***** Use onos-lib-gen *****\n");
 
             // rule to publish the onos dependency pom
-            writer.write("\npass_thru_pom( \n" +
+            writer.write("\npass_thru_pom(\n" +
                          "    name = 'onos-dependencies-pom',\n" +
                          "    src = 'pom.xml',\n" +
                          "    out = 'onos-dependencies.pom',\n" +