fix IterationJob#round_for_eval to use some kind of #ceil for integers
fix IterationJob#round_for_eval to use some kind of #ceil for integers

* should be equivalent to (iterations.to_f / repeat_eval).ceil * repeat_eval
* but without needing floats
* also supports repeat_eval to be 1
* could be done with modulo, but would need a conditional

jruby/perfer