improve storage unit tests

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9769 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
minor logging improvement

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9770 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda