sheep: reduce auto recovery log

Currently, auto recovery process produces one log message per one object.
The log messages consume too large disk space when a cluster has many
objects. This patch reduces the disk consumption by printing progress in a
style of percentage. The existing message is logged in debug level.

Signed-off-by: Saeki Masaki <saeki.masaki@po.ntts.co.jp>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
sheep/recovery: fix floating point error

Once the recovery count is less than 100, sheep process will crash
because of devided by zero.

The solution is round up the recovery count first to make sure
the result is not zero.

Cc: Saeki Masaki <saeki.masaki@po.ntts.co.jp>
Signed-off-by: Ruoyu <liangry@ucweb.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>