iohub keyboard mappings for windows complete

.key and .char mapping as expected from tests so far.

Note: On Windows, when numlock is OFF, numlock key values == main key
values at every level, so the two can not be differentiated. Therefore
numpad .key values do not have 'num_' prefix.
Merge branch 'master' of git://github.com/psychopy/psychopy
Merge pull request #691 from isolver/master

iohub keyboard mappings for windows complete