wrap-producer-promise to accept callbacks rather than async state instance

[incepter]

[incepter]

Closing #57

[incepter]

should this land ?

the problem is on run and runp when encountering a producer, they create an instance for that then subscribe an run it. this allows the props object's creation.

to finalize this task, we need a way drill down the props object

[incepter]

not relevant anymore