I had mispelled "absorptance" as "absorbtance" in many cases, which added confusion to already confusing distinctions.  Fixed throughout.

Renamed AbsorbtanceToAbsorbance and AbsorbanceToAbsorbtance to be correct.  The old routines are still there for backwards compatibility, and they call through the renamed ones.

I ran a number of the relevant tests (NomogramDemo, IsomerizationsInEyeDemo, IsomerizationsInDishDemo, CIEConeFundamentalsTest) and none are broken, so I think my big search and replaces worked correctly.

Signed-off-by: David Brainard <brainard@psych.upenn.edu>
Merge branch 'master' of https://github.com/Psychtoolbox-3/Psychtoolbox-3
Added debugging output for PR-670 branch, when it fails to connect.  DHB, MS

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