Timo-zappa

* Add Async Task Support! Lots of tickets and PRs related, including 61, 603, 694 and 732.
* More info here: https://blog.zappa.io/posts/zappa-introduces-seamless-asynchronous-task-execution
* Fix Django non-WSGI function initialization, 748
* Add support for AWS Lambda Dead Letter Queue, 740
* Fix API Gateway test button (the bolt button), 735
* Switch to using per-lambda-name (project-stage) rather than a single default LambdaExecutionRole

* Fix broken Let's Encrypt trying to use new ACM ARNs
* Add `apigateway_description` setting, fixes 722
* More aggressive virtualenvironment checking

* Add `certificate_arn` setting, support for AWS Certificate Manager (710)
* Fix zip permissions when building on Windows (714)
* Change the active working directory to `/tmp` when using the slim handler so that relative filepaths work. (711)

* Hotfix for broken Django deploys

* Add confirm to `certify`
* Add `--manual` to `--certify`
* Fix `certify` for existing domains
* Add `extra_permissions` setting
* Add `shell` command

* Revert to Kappa 0.6.0 684 and others
* Add binary support for more HTTP methods, 696