v1.2.2, 2015-02-27 -- Bug fixes. Stop using deprecated properties:
                      BaseException.message and mimetype keyword in render_to_response
v1.2.1, 2013-11-14 -- Confirm payment before sending email
v1.2.0, 2013-10-22 -- Retry after 2 sec if PATCH request failed. Catch send mail exception.
v1.1.0, 2013-10-18 -- Send confirmation email to client after successful payment. New settings: VTIXY_MAIL_FROM_EMAIL,
                      VTIXY_MAIL_FROM_NAME, VTIXY_MAIL_SUBJECT_PREFIX, VTIXY_MAIL_TICKETS_URL
v1.0.2, 2013-09-27 -- Security bug. Add VTIXY_ASSIST_TEST_MODE setting to permit test payments or not.
                      Pass only 'Delayed', 'Approved', 'PartialApproved', 'PartialDelayed' order states.
v1.0.1, 2013-09-17 -- Patch order with transaction_id (billnumber)
v1.0.0, 2013-09-11 -- Initial release.