[stripe] description in template must have default val.
[request] add cancel request.
Merge pull request #244 from formapro-forks/stripe-checkout-description-must-have-default-val

[stripe] description in template must have default val.
Merge pull request #245 from formapro-forks/request-cancel

[request] add cancel request.
Release 0.12.4
Merge branch '0.12'