Add email verification to the metrics that go to kpiggybank.

fixes #3528
Send /wsapi/stage_* events to the KPI backend.

* Add tests in tests/kpi-test.js to ensure both staging and completion events are added to the queue.

fixes #3920
Allow UA to submit arbitrary claims to assertion
correctly test claims is an Object
Add unit tests for the expected behavior of experimental_allowUnverified.

* Fix a problem with validateUserAssertedClaims where everything but objects were allowed. Only objects should be allowed.
Add Luke Howard to the CONTRIBUTORS list.

fixes #2910
Merge branch 'lhoward-userAssertedClaims' into dev
Ensure the rp name is specified even if no siteName is specified for check_registration and verify_primary_user.

fixes #3976
Merge branch 'issue-3976-undefined-sitename' into dev
Issue 2647 fixed.
_include.js modified and issue 2647 fixed.
Changes made.
Add the isNull, isString, and isUndefined checks to _include.js

* Add unit tests for isNull and isUndefined
* remove the _ from is_Undefined and is_Null
Add tests for loggedInUser type when calling navigator.id.watch
Merge pull request #3968 from shane-tomlinson/issue-3528-email-verification-metrics

email verification metrics
Clean up the tests slightly
Merge pull request #3979 from shane-tomlinson/issue2647

Issue2647

A pleasure working through this with you, @mohit-agarwal! Thank you very much for the contribution! 

r+
Add statsd metric for looking up /.well-known/browserid

fixes #1704
report success and failure cases separately for fetch_well_known and deep_fetch_well_known statsd metrics.