fix compiler warnings, workaround const_correctness in material update (TrkExEngine-00-00-38)

	* fix warnings in StaticNavigationEngine
	* use const_cast to update parameters with material effects
	* tag as TrkExEngine-00-00-38

2015-11-04 Noemi Calace <noemi.calace@cern.ch>
        * Adding direction in the energy loss calculation
        * tag TrkExEngine-00-00-37

2015-10-26 Noemi Calace <noemi.calace@cern.ch>
        * Updating configuration of the AtlasExtrapolationEngine
	* Making changes for propation to the endlayer
        * tag TrkExEngine-00-00-36

2015-10-16 Sharka Todorova <sarka.todorova@cern.ch>
           * first import of StepEngine
	   * updates in ExtrapolationEngine/StaticNavigationEngine
           * tag TrkExEngine-00-00-35

2015-08-04 Shaun Roe
	* fix coverity defects
...
(Long ChangeLog diff - truncated)


Former-commit-id: f8f9e563