sensor_orientation_ not set to identity

[nfioraio]

LZFDepth16ImageReader and OpenNIGrabber do not leave to identity rotation the sensor_orientation_ field of the cloud, giving incorrect visualization when the rotation is applied (see pull request #92 and issue 116 #116).

[jspricke]

Hi Nicola, thanks for the patch. Some comments:

• Could you please remove the merge.
• Please don't remove all the whitspaces. I know they are annoying, but your actual changes are hard to find in all these trivial ones. Also, it would result in attributing all the lines to you in a git blame. Removing them in the lines you are changing anyhow is fine, though.
• As far as I can see, Radu originally added the initial values to fix compiler warnings. So I guess it would make sense to put identity values in instead. Could you please change that? Otherwise, please don't send patches with commented code, just remove it (we have git to get the old code back ;) ).

Thanks!

Jochen