add sha3 calculator

Signed-off-by: Mattias Andrée <maandree@operamail.com>
some trim down

Signed-off-by: Mattias Andrée <maandree@operamail.com>
forgot the .h

Signed-off-by: Mattias Andrée <maandree@operamail.com>
m

Signed-off-by: Mattias Andrée <maandree@operamail.com>