Add toString method to WorkflowServiceStubsOptions

[tsurdilo]

improvement request to add toString method to WorkflowServiceStubsOptions that would print out all options available. can be extended to any/all other options type of classes

[dskarbek]

Please make sure to add a toString method to the Builder sub-class as well so we can log what options we are building with.

[Quinn-With-Two-Ns]

We should also include equals and hashcode like all other *Options in the Java SDK. The Builder can be converted to a WorkflowServiceStubsOptions to be logged so you will get an accurate log of what options are actually set logging the Builder does not.

[Quinn-With-Two-Ns]

We also need to do this for OperatorServiceStubsOptions though that is much less frequently used.

[dskarbek]

The Builder can be converted to a WorkflowServiceStubsOptions to be logged

So long as there's no failures that the build method will trigger on a partially filled out Builder.