Avoid using namespace std in header files.
openni_pcd_recorder: Add command-line support for device IDs (like in openni_viewer).
openni_pcd_recorder: Improve calculation of default buffer size.
Merge pull request #674 from yangyanli/avoid_using_namespace_std_in_header

Avoid using namespace std in header files.
Merge pull request #673 from j-oberlaender/pcd_recorder_improvements

Pcd recorder improvements