message: Add creating slot to output channel
diff: @@ -40,6 +40,7 @@ export async function createSlot(root: ISiteTreeRoot, existingSlots: AzureTreeIt
  context.showCreatingTreeItem(slotName);
  const creatingSlot: string = localize('creatingSlot', 'Creating slot "{0}"...', slotName);
  + ext.outputChannel.appendLog(creatingSlot);
  return await window.withProgress({ location: ProgressLocation.Notification, title: creatingSlot }, async () => {
  return await client.webApps.createOrUpdateSlot(root.client.resourceGroup, root.client.siteName, newDeploymentSlot, slotName);
  });
  