add boring config.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>
update compass and sass version.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>
all conf can overwrite default value on config.rb file.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>
test overwrite config.rb config.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>