Make `update` for the whole project dir instead of each updated dir

Alter pull request #49.

There were still issues with `gitcc rebase` and new files in several
subdirs. `lshistory` for such elements is reversed i.e. subdirs first
and then parent dirs.
Merge pull request #50 from phts/fix-fix-rebase-new-files

Make `update` for the whole project dir instead of each updated dir