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.