coordination: add option to jump into state-machines

by passing the argument :starting_state the user can choose
states in which a statemachine should start.

These states needs to be dinfed within the statemachine as:

prepare_jumpin("wall" => wall1, "pipeline"=> pipeline1)
Why testing using nil?. It suggests that "false" would be a valid return value.

Use "if x" and "if !x" in Ruby unless you have a compelling reason to explicitly test against false and nil.

While you are at it, split the if and the assignment (i.e. first assign to start_state then test in the if). This is a very long line...