Added Feature2D::generateKeypoints3D() for convenience.
Added parameter "Vis/PnPOpenCV2".
Added parameter "Vis/ForwardEstOnly".
Removed OdometryOpticalFlow class, replaced by OdometryF2F (frame-to-frame). To get the same previous OpticalFLow approach, parameter "Vis/CorType" should be set to 1.
Some parameters under group "OdomFlow/..." are now under "Vis/CorFlow...".
In Registration class, add computeTransformationMod() method to modify input signatures.
Added constructor Signature(SensorData) for convenience.
Modified words multimap used with cv::Point3f instead of pcl::PointXYZ to limit the use of PCL headers where they are not really required.
Added Stereo::create() for convenience.
Transform: fixed quaternion constructor where data_ was not initialized. Added parentheses operator for convenience.
DatabaseViewer: loading .rtabmap/rtabmap.ini instead of .rtabmap/dbViewer.ini when used from rtabmap application. Added vertical layout option for convenience.
MainWindow: fixed wrong Odometry speed values
ParametersToolBox: using QStackedWidget instead of a QToolBox for space, added "Restore Defaults" button.
