test cases to expose issue #19
clean up GitRepo.ls() a bit
fix bug in GitRepo.ls() when path ends with / and directory=False

non-directories were being ignored
fix issue #19, fix HgRepo.log() with directory=True on non-root paths
Merge branch 'develop' into ls-report-commit
add test cases for VCSRepo.ls() with commit in report
correctly report commit on root
report commit in HgRepo.ls()