Improve Executors related logging behavior

- Specify Logger for the Executor
- Use Executor#execute instead of ExecutorService#submit for
  fire and forget type of usage.
   Note: submit() will swallow thrown Exception

Change-Id: I507b841dc3feedf4ad20a746c304518d68fb846a
diff --git a/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java b/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java
index 1792bce..8e36ea9 100644
--- a/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java
+++ b/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java
@@ -138,11 +138,11 @@
     }
 
     private void registerDeviceResource(Device device) {
-        executor.submit(() -> adminService.register(Resources.discrete(device.id()).resource()));
+        executor.execute(() -> adminService.register(Resources.discrete(device.id()).resource()));
     }
 
     private void unregisterDeviceResource(Device device) {
-        executor.submit(() -> {
+        executor.execute(() -> {
             DiscreteResource devResource = Resources.discrete(device.id()).resource();
             List<Resource> allResources = getDescendantResources(devResource);
             adminService.unregister(Lists.transform(allResources, Resource::id));
@@ -151,7 +151,7 @@
 
     private void registerPortResource(Device device, Port port) {
         Resource portPath = Resources.discrete(device.id(), port.number()).resource();
-        executor.submit(() -> {
+        executor.execute(() -> {
             adminService.register(portPath);
 
             queryBandwidth(device.id(), port.number())
@@ -198,7 +198,7 @@
     }
 
     private void unregisterPortResource(Device device, Port port) {
-        executor.submit(() -> {
+        executor.execute(() -> {
             DiscreteResource portResource = Resources.discrete(device.id(), port.number()).resource();
             List<Resource> allResources = getDescendantResources(portResource);
             adminService.unregister(Lists.transform(allResources, Resource::id));