Use apache commons Pair instead of javafx

It looks like javafx does not have Pair when using OpenJDK.

Change-Id: I3379dc87e0515185714b28ca0832a36b76b0772f
diff --git a/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireCodec.java b/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireCodec.java
index 755cb68..00d20a7 100644
--- a/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireCodec.java
+++ b/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireCodec.java
@@ -17,7 +17,7 @@
 
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
-import javafx.util.Pair;
+import org.apache.commons.lang3.tuple.Pair;
 import org.onlab.packet.MplsLabel;
 import org.onlab.packet.VlanId;
 import org.onosproject.codec.CodecContext;
diff --git a/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireWebResource.java b/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireWebResource.java
index e20d282..854697b 100644
--- a/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireWebResource.java
+++ b/web/src/main/java/org/onosproject/segmentrouting/web/PseudowireWebResource.java
@@ -19,7 +19,7 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
-import javafx.util.Pair;
+import org.apache.commons.lang3.tuple.Pair;
 import org.onlab.util.ItemNotFoundException;
 import org.onosproject.rest.AbstractWebResource;
 import org.onosproject.segmentrouting.SegmentRoutingService;
@@ -168,7 +168,7 @@
             L2TunnelHandler.Result res = srService.addPseudowire(pw);
             if (!(res == L2TunnelHandler.Result.SUCCESS)) {
                 log.trace("Could not create pseudowire {} : {}", pw.l2Tunnel().tunnelId(), res.getSpecificError());
-                failed.add(new Pair<>(pw, res.getSpecificError()));
+                failed.add(Pair.of(pw, res.getSpecificError()));
             }
         }