BF: iohub calibration for Tobii 'space' key

Associated events for space key not triggering, as key mapping was wrong
following 1.81 keyboard event changes. Specifically, key == 'space' was
being checked, when it should be  key == u' '
BF: iohub eyelink calibration mode keyboard events

Some keyboard based events not triggering during eyelink calibration
process, as some key mappings were wrong following 1.81 keyboard event
changes.
ENH: Added theeyetribe to gcCursor demo io config
Removed print
BF: gcCursor coder demo keyboard device label

to work around a iohub Tobii calibration bug, keyboard device label must
be 'keyboard'.
ENH: Simplified stroop_eyetracker builder demo.

Also verified it still worked. ;)
ENH: Updated gcCursor demo use new keyboard funcs
Merge pull request #729 from isolver/master

BF: iohub eye tracker calibration (for tobii and eyelink) keyboard event fix