CDRIVER-4801 support named KMS providers (#1509)

* copy in new unified tests

* copy in new legacy spec test

* add new KMS providers to test runner

add partial support for JSON schema 1.18

* implement `encrypt` and `decrypt` operations in unified test runner

* export env vars in run-tests.sh

* update prose test 11 for named KMS providers

* add map for TLS options

Required to configure TLS options on named KMS providers

* check out libmongocrypt with changes of MONGOCRYPT-605

* update docs to reflect spec terminology

KMS provider is specified with string `<KMS provider type>` or `<KMS provider type>:<KMS provider name>`