Skip results if testing was incomplete on unload

If a user navigates away from a page on which bandwidth is being tested
(i.e. before the file download probes are finished), the accuracy of
the results vary widely.

Therefore, don't save or report bw results if testing didn't complete
before user navigates off page.

A side-effect of this change is that bw testing will run on subsequent
pages until it finishes (which only requires that a user remain on a
page for 15s, so valid data should come quickly).

(cherry picked from commit 546889fa9f077b683c0dbdd39404e207a98760d0)

Signed-off-by: Philip Tellis <philip@lognormal.com>
read from cookie every time init is called since cookie name might change
update iframe loader in README
Ignore clicks on flash objects

Chrome for Linux using PepperFlash tends to bubble click events between
flash and JavaScript.  This causes problems if the flash object requires
the ability to handle multiple fast clicks and boomerang spends some
time figuring out what the target of the click was.

This patch ignores clicks if they occurred on a flash object.
fix a whole bunch of jslint errors
Merging changes from upstream master