Recommend that the sandbox be a clean checkout.
Fix issues updating cvs tree before import.

- Use -Q rather than -q so that conflicts can be logged.
- Capture stdout and log both it and stderr if the cvs operation fails.
Need to do case insensitive matching when matching filenames.

Want the case-sensitivity to be a property of the InclusionMatcher, so make it take
strings instead of Regex objects.
Don't assume a CVS process has failed if it prints to stderr.

Also, sort out line-endings when gathering the process' output.
Allow options to be specified when initialising the git repository.
Merge branch 'dev' for v1.2.0 release