v1.0.5-beta.1

This release adds support for (PSR-16: Common Interface for Caching Libraries)[https://www.php-fig.org/psr/psr-16/] cache adapters, and includes a new NullGrantType for manually specifying an access token without a method for retrieving a new one (see the README for more details). This is beta because I may be adding one more change to the final release of 1.0.5.