Fixed setCameraPosition in PCLVisualizer.

After setting the new camera position the camera clipping planes
where not adjusted which resulted in a black render window.
The site which pointed me in the right direction was
http://www.vmateevitsi.com/2011/10/25/vtkcamera-problem-with-setposition/
Merge pull request #872 from nylocx/cameraPoseFix

Fixed setCameraPosition in PCLVisualizer.