Board design patch — Word Attack Steam update #258999

Made some changes to the way the board designer saves the data. Instead of relying on recreating the same arrangement of cell ids when using the board, will now save shape data. Also changed the way cell edges are formed when using boards formed from board backgrounds, because the way the data is stored is no longer the same as the original mechanism (eg the Marble board). Therefore the effect should now look the same in both cases.