FIX #2222317 by @keule: Set the default value for payment method only form gets built, not when submitted
FIX #2126871 by @checker: avoid a possible database deadlock
FIX #2115777 by @checker: Notice on review page if payment pane isn't there
FIX #2114029 by @haggins: Fix a notice which occurs when you return from a different payment method
FIX #2106269 by @checker: Round the amount to make sure it always complies with the API definition which requires 8.2 decimals
As usual, this is mostly an update of Drupal core and contributed modules, and all users are recommended to update ASAP. There are also several bug fixes, mostly having to do with the mechanism by which an Incubator site may be disabled, and a new feature: there is now an easy way for site administrators to turn on a site-wide contact form.