math.runge-kutta: fix help-lint.
math.runge-kutta: fix help-lint.

tgunr/factor,mrjbq7/factor,factor/factor,mrjbq7/factor,mrjbq7/factor,mrjbq7/factor,factor/factor,factor/factor,tgunr/factor,tgunr/factor,factor/factor,mrjbq7/factor,tgunr/factor,tgunr/factor,tgunr/factor,mrjbq7/factor,factor/factor,factor/factor