SERVER-13712 smoke.py --clean-every=N option
SERVER-13712 cleanbb should clean entire /data/db dir

Invoke cleanbb via function call, not subprocess.

clean_dbroot() now cleans entire /data/db if --with-cleanbb specified,
including periodic cleanups.
SERVER-13712 fix fedora8 builders (python 2.5.1)
Merge remote-tracking branch 'upstream/master'