better logging of objects to console
add flag mentioning that boomerang was loaded late
add check for boomerang loading too late, and massage load time in that case
Run memory test on ajax beacons too, and collect fresh data at that time
Once beacon has been sent, remove parameters that should only be beaconed once and have been sent
Instrument XMLHttpRequest calls

Add a new plugin that instruments the global XMLHttpRequest object
when called to wrap timing information around it.  The loadEnd event
will result in an xhr_load event firing with all timing and resource
information included as part of the data object.

We also create a MutationObserver if possible to check if the XHR call
resulted in any other resource downloads.

Additionally, we instrument all clicks to see if they resulted in script
downloads which could indicate AJAX using dynamic script nodes.
handle case where page author uninstruments and then reinstruments auto xhr
Get load time start & end from detailed XHR object

If we have detailed timing information in the XHR object, then use it
to determine load time start and end.

Also, set subresource flag after we've determined times.
Send HTTP response status on beacon if available

If the detailed XHR object contains an HTTP status code and if the code is
not 200, then include it on the beacon as the http.errno parameter.
Use detailed XHR object to determine first byte time

With a detailed XHR object, we can also determine first byte time,
so pull out that information and add it to the beacon.
Refactor a bit to remove code duplication
Beacon detailed XHR data

If the browser supports ResourceTiming, then we can pull detailed NavTiming like
data from the ResourceTiming object.  If not, we'll use the different readyState
states as proxies if they're available.
status is a number.  also beacon http method if not GET
use the correct variable
allow overriding main page url

auto-xhr beacons will now include the url of the xhr call instead of the
main page
fire onbeacon immediately rather than after beacon is sent
actually use the API correctly
Call sendBeacon for xhr beacons as well

And only subscribe to events once
remove unset keys
xhr timers should only be checked when called from xhr load