svn verify: add a test for corrupt repositories. This case contains a couple of unlikely (but not impossible) failure cases that the code previously did not handle. The verifier is updated to address these, and the output made a bit more consistent.

#!/bin/sh
. $(dirname $0)/common.sh

for b in `hg branches -aq` ; do
    hg co $b || break
    echo verifying $b
    hg svn verify
done