Count number of corrupt lines + allow non-existent files to be… (#4631)
Count number of corrupt lines + allow non-existent files to be… (#4631)

Fixes #4612.
letsencrypt/boulder,jsha/boulder,bmw/boulder,jsha/boulder,bmw/boulder,bmw/boulder,jcjones/boulder,jsha/boulder,letsencrypt/boulder,jcjones/boulder,jcjones/boulder,jcjones/boulder,letsencrypt/boulder