For nodes that are generator based, let them self enforce stop patterns or exhaust

[iantbutler01]

Right now if you have a node that yields anything you must have a second node that decides to jump back into that node for it to continue yielding. That is useful in complex cases like code analysis or any type of output checking, but in simple cases like greeting a user with streaming the need for flow control is tedious as it should just stream through to exhaustion.

To that end we should let users both A. run a node to exhaustion without flow control. B. Allow ways to configure a callback to decide if the next step in execution should be moved to as this would obviate the need for the second node entirely.