Small change -- make transparent Gamepiece still responsive to click and
hover events in preparation for the event handling coming up.
Gamepiece now responds and placePiece functions properly. Clicking
anywhere on a column will 'drop' a piece (temporarily hardcoded to a red
one) into the clicked column.

***STACK OVERFLOW OCCURRED!***
Fixed by turning base type of Color into char to save space, but may
come back to haunt.
***NOTE HERE FOR FUTURE REFERENCE***

***TURNING POINT***
If want to add a single widget to do slots and signals for all the
Gamepieces, this is where it should have been implemented. *Technically*
should be able to simply brance and merge with git, but just in case.
***NOTE HERE FOR FUTURE REFERENCE***