Updated blinky.js

Fixed pin reference to use array type, added some comments, and
changed blinky() to take the pin as an argument rather than having it
hard coded in the function itself.

Change-Id: I6905fbc28d95462503291f3f3d26f4d1f80f8879
Signed-off-by: Marcello Lioy <mlioy@qce.qualcomm.com>
Merge "Updated blinky.js"