v1.21.0

Add the strict_order_by parameter as an sqlc configuration option

Also, I belatedly realized that we were matching our rules versions with the version of the sqlc binary. Apologies for breaking that convention.

To create the smallest correct tarball for the release:

1. Down one of the source archives and extract it (this will eliminate all of the git cruft)
2. Cd into the root directory of the archive
3. Create the tarball of the sqlc directory: tar czvf rules_sqlc.tar.gz sqlc
4. Take the sha256 sum of the tarball: sha256sum rules_sqlc.tar.gz
5. Upload the tarball as a binary to your release
6. Update your WORKSPACE file with the link and sha256 sum of the tarball