V2.0 swift feature branch for merge into v2.0

TODO for this PR to get merged:

- ~~Add documentation for Image Resizer~~, Jazzcat, and Unblockify
- ~~Add project slug as arguments to resizeImages and combineScripts~~
- ~~Add tests for Jazzcat~~
- ~~Add tests for Image Resizer~~
- ~~Merge in cache parameter for resizeImages~~