[fix bug 835781] Implement session based authorization

* Add the ability to authorize API requests depending on current user session.
* Expose bugzilla email as a restricted field.
* Fix test_csv_export filename format
Merge pull request #339 from johngian/835781

[fix bug 835781] Implement session based authorization
Merge pull request #340 from akatsoulas/837400

[fix bug 837400] Ability to login if a vouched mozillian.
[fix bug 832955] Implement date range selector in /events/
Merge pull request #337 from johngian/832955

[fix bug 832955] Implement date range selector in /events/
[fix bug 837402] Dashboard for mozillians.