Fix description for Checkstyle
Hide output of diff when called from Run
Make relpath()

This should *not* be in CheckStyleFilter. But it’s where it’s used, so,
for now, it lives here.

Damn squatter...
Enable output of check style as a table

With a second output format, it’s getting closer to time to add a new
layer to extract out the formatting. Next one. I promise.
Let run command determine output format