Readjust the indentation of mon_clock_skew_check.py and mon_thrash.py.
Added docstrings.

Fixes: 6537
Signed-off-by: Warren Usui <warren.usui@inktank.com>
Merge pull request #192 from ceph/wip-6537-wusui

Readjust the indentation of mon_clock_skew_check.py and mon_thrash.py.