Crossword v1.40

Unless bugs are found and reported I expect this will be the final release of the game.

v1.31 - pause clue scroll timer when checking or removing errors

        do not reset board origin after clearing errors

v1.32 - select current cell after removing errors

v1.33 - added support for REBUS marked section - circle marked cells (experimental)

        (to disable a menu option is available)

v1.34 - add 'show letter' menu option to fill in the current cell

v1.40 - public release