Zappa

* Adds `--non-http` to `tail`

* Fix 64bit `lambda-packages` (645)
* Fix wheel packages (642)

* Replace ZappaCookie with Set-Cookie permutation! :D (636)
* Bump `lambda-packages` version
* Fix installed_packages_name_set (637)
* Add `slim_handler` (548)
* Various small requirements bumps and other fixes.

* Adds `--since` and `--filter` to `tail`
* Fixes `unschedule` command when used with specific stage

* Adds `package` command
* Forbids the use of unicode environment variable keys
* Initialize wsgi.errors to sys.stderr (was '')
* Accept `AWS_SESSION_TOKEN` when executing via an IAM role (589)
* Set `REMOTE_USER` even when using `iam_authorization`
* Rename `lets_encrypt_schedule` to `lets_encrypt_expression` (571)
* Messages in `tail` are now sequential
* Bump version requirements, update README
* Various other small changes

* File `tail` broken in CLI refactor