Just some comment changes.

Signed-off-by: David Brainard <brainard@psych.upenn.edu>
Moved all tutorials into subdir xNeedChecking.

Created empty dirs where the tutorials will go.

The idea is to run each tutorial and make sure it still works, then move it from xNeedChecking up one level.  Soon we will know they all work, or which ones are broken and need fixing.  Ones that need fixing can go into a dir called xNeedFixing and await their removal from purgatory.

Signed-off-by: David Brainard <brainard@psych.upenn.edu>
Working on updating t_colorSpectrum

Almost done, but need to figure out how isetbio inverts a display lookup table.

Signed-off-by: David Brainard <brainard@psych.upenn.edu>