Added numPadView.  Having trouble get padding on the tops of buttons.  No target action for numPadView is set up yet.
Fix numpad formatting, add highlight and target-action methods for num pad button being pressed
Grid is now populated with values but the row and column are being switched somewhere.
Fixed row/column switching problem, wrote method to check validity of solution
Finished implementation.
Ran Clang and OCLint
Merge pull request #1 from RMacfarlane/GridEditable

Grid editable