Fixed missing side effects of secondary equations.

When secondary equations have a side effect on main state in Ordinary
Differential Equations integration, it is now preoerly taken into
account.

JIRA: MATH-960

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1463680 13f79535-47bb-0310-9956-ffa450edef68