opentelemetry.sdk.trace.Cleanup methods should support SDK tracer provider input

[duncanpo]

opentelemetry.sdk.trace.Cleanup.shutdown and forceFlush currently support only opentelemetry.trace.TracerProvider objects as input. If passed in an SDK version (opentelemetry.sdk.trace.TracerProvider), they will fail.

The rationale was SDK tracer provider class has its own shutdown and forceFlush methods. However, we should generalize opentelemetry.sdk.trace.Cleanup to support both API and SDK TracerProvider objects.

[duncanpo]

In metrics branch