enh(memory leak testing): added a test case

If you navigate to http://localhost:9002/misc/demo/leak-testing.html you
will see a leak testing demo page.

The process on Chrome, using the profiler from Chrome developer tools, is:

1. Navigate around the pages a bit to cache whatever Chrome might cache
2. Go to the home page
3. Take a snapshot from the profile tab
4. Go to the noOptions page
5. Return to the home page
6. Take another snapshot on the profile tab
7. Select to display the difference between snapshot 1 and 2 (right below the menu bar in the profile tab).  At present you'll see about 250K of retained memory
Merge pull request #2022 from PaulL1/memory_leak

enh(memory leak testing): added a test case