fixed bug with laser passing between two diagonally placed DF polarizers

fixed bug with laser passing between two diagonally placed DF polarizers

This reverts commit f00dbcf8.

The behaviour "fixed" in the above commit as being a bug is in fact
the correct and intended behaviour, as Deflektor style polarizors are
to be treated as solid, tile-filling blocks, not as tiles with a
little bit free space around them, as suggested by the graphics (and
as it is the case with the Mirror Magic variant of these tiles).