Adding Flawfinder to Patchwatcher

[Austin English]

I had a discussion with Dan about adding Flawfinder to the
patchwatcher. Currently, it's got some pretty generic errors, but it
seems able to test only patches, so we wouldn't be flooded with old
nonbugs (or we could set up a blacklist of safe errors). For
reference, I've run it on today's git. I'm attaching the full log, as
well as a condensed version of the most common errors (1 per error
type). Looks like a lot of chances for buffer overflows..

Thoughts?

-Austin