Minor stylistic changes made to the Boost Build test/clean.py test script. Corrected the second test case the --clean option was getting tested instead of --clean-all.
See the trac ticket http://zigzag.lvk.cs.msu.su:7813/boost.build/ticket/198 on what still needs to be improved with this test.
[SVN r47970]
Jurko Gospodnetić