Better error message when a initial state is not part of the given state machine.
Better error message when a initial state is not part of the given state machine.

bryanedds/FSharpx.Extras,bryanedds/FSharpx.Extras,sideeffffect/FSharpx.Extras,sideeffffect/FSharpx.Extras,bryanedds/FSharpx.Extras,fsprojects/FSharpx.Extras,fsprojects/FSharpx.Extras