Defect corrected: when 3D volume is converted to 4D using the "MainMenu>Volume>Convert 3D to 4D" function, dynamic information (such a timepoints) is not set properly in the new volume.

Developing UI function:   " MainMenu>Volume>Crop timepoints".  This function takes 4D volume.
User specify comma-deliniated set of timepoints such as "1,3,5,7".  Function outputs another 4D volume containing only the specified timepoints. This is a very important function for troubleshooting the 4D registration.