Made the move tool iterational

Now the tool does not create new layers and does not create
numerous undo commands. It works in an iterational way: you move
the node (or selection) as many times as you wish. After the moving
done and you switch the tool (or apply any other action) the move
stroke will be finished and added to your undo history.

Please test it in 'krita-new-move-tool-kazakov' branch.