add Makefile

Signed-off-by: MORITA Kazutaka <morita.kazutaka@gmail.com>
remove guilt dependency

Signed-off-by: MORITA Kazutaka <morita.kazutaka@gmail.com>
add test

Signed-off-by: MORITA Kazutaka <morita.kazutaka@gmail.com>
stop udpating refs

Signed-off-by: MORITA Kazutaka <morita.kazutaka@gmail.com>