With the previous change of starting a tap on a drag,
we removed the GestureDetector from all squares with any pieces.
This included the opponent's pieces. Tapping and taking an opponent's
piece was not possible anymore.
This was a bug, since we still want to detect a tap and take an opponent's piece.
This adds an option to dragging-and-dropping which is slightly hard on
smaller screens.
Fix promotions when tapping and fix handling of subsequently tapping two pieces of your color
Cancel tap if a drag is started (tapped square will not stay red in case a drag is started)
Change url strategy back to the hashtag thing
Change version
Fix bug that would not allow a piece move if you tried to take an opponents piece.
Fix the coloring of the last move after an invalid move was played.
Upgrading deps
