message: derive Clone for ArgminParameter
diff: @@ -13,6 +13,7 @@ use prelude::*;
  use parameter::ArgminParameter;
  /// This struct hold all information that describes the optimization problem.
  +#[derive(Clone)]
  pub struct ArgminProblem<'a, T: ArgminParameter + 'a, U: ArgminCostValue + 'a, V: 'a> {
  /// reference to a function which computes the cost/fitness for a given parameter vector
  pub cost_function: &'a Fn(&T) -> U,
  