Logical multiplication

Returns A AND B :

 A  |  B  |  A AND B
 ---+-----+-------
 0  |  0  |    0
 0  |  1  |    0
 1  |  0  |    0
 1  |  1  |    1

 Example :  and( 0b1101, 0b1011 ) -> 00001001

 Syntax : < x > & < y > | et( x, y ) | and( x, y )