Fix some tests which were pointing to the wrong script path
Update player sprite mappings & png file: includes gun animations
for each of left foot forward, still, and right foot forward.

Update sprite map code to navigate three possible levels of
sprites json mapping: the first level is "direction" (forward, back,
left, right), the second level is "position" (right foot forward,
still, left foot forward) and the third (optional) level is
"action" (basic, hand raising, gun shooting,...)

The code all works with the above changes: now to update sprite
mappings for the gun animations json and animation definition
for shooting.