applied travis-ci

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
add retrieve backup object command

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
increase version and update documents

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Merge branch 'devel'