Recognise UUID4 passed instead of object for get operations

[Chaffelson]

It would be helpful to users if a UUID for an object instead of the whole object could be passed to functions transparently. In this way the function could fetch the object by UUID rather than throwing an error.
This is an improvement because use of UUID or whole object is inconsistent across the code-base, as functions were built based on what the underlying NiFi calls expected, rather than what was consistent for the user.