message: Core: minor change to n_iterations_log.
  If set to zero or less, it now once more means that no steps will be made inbetween start and finish.
  Also set minimum number of iterations to 1.
diff: @@ -23,8 +23,10 @@ namespace Engine
  {"force_max_abs_component", {this->force_max_abs_component}} };
  // TODO: is this a good idea?
  - this->n_iterations = this->parameters->n_iterations;
  - this->n_iterations_log = std::max(long(1), std::min(this->parameters->n_iterations_log, this->n_iterations));
  + this->n_iterations = std::max(long(1), this->parameters->n_iterations);
  + this->n_iterations_log = std::min(this->parameters->n_iterations_log, this->n_iterations);
  + if( this->n_iterations_log <= long(0) )
  + this->n_iterations_log = this->n_iterations;
  this->n_log = this->n_iterations / this->n_iterations_log;
  // Setup timings
  