Merge branch 'ab/cond-skip-tests' into maint

A few tests were run conditionally under (rare) conditions where
they cannot be run (like running cvs tests under 'root' account).

* ab/cond-skip-tests:
  gitweb tests: skip tests when we don't have Time::HiRes
  gitweb tests: change confusing "skip_all" phrasing
  cvs tests: skip tests that call "cvs commit" when running as root