Remove clamav support and reduce build disk use.
Remove the build dependency on clamav-devel so that cyr_virusscan and
such aren't built. Clamav still uses the old openssl libraries, and so
cyr_virusscan would occasionally segfault. This caused a Cassandane
failure on ppc64. (I have no idea why it only failed there.)
Add --cleanup to the testrunner.pl command line to keep disk usage
lower, This may help to fix an intermittent test failure which was
potentially related to disk space.
Bump to 3.0.1-3.