Plus and SlicerIGT now supports color image acquisition and display

SlicerIGT and the Plus toolkit now supports color image acquisition, streaming through OpenIGTLink, and live display in 3D Slicer. This allows using SlicerIGT to display color Doppler ultrasound images, endoscopy, and other full-color video during image-guided procedures. Currently Epiphan, ImagingControls, and any Microsoft Media Foundation-compatible framegrabber devices are supported. Thanks to Adam Rankin, the key developer of this feature.