Handle a missing "cvs" binary better.
Review Request #886 — Created June 7, 2009 and submitted
Handle a missing "cvs" binary better. In our dependency checks, SCMTool and unit tests, we didn't handle a missing "cvs" binary in the same way we do for many of our other dependencies. I noticed this because Ubuntu doesn't install CVS by default anymore (hooray!). This change fixes up all the places so that we don't throw errors.