add gif-burst

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

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

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

Signed-off-by: Mattias Andrée <maandree@operamail.com>
add coreutils as a dependency for pdf-unpage

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