fixup! virt: aexpect code cleanup

Signed-off-by: Chris Evich <cevich@redhat.com>
virt: aexpect server should log exceptions

Signed-off-by: Chris Evich <cevich@redhat.com>
virt: more aexpect unittests

Signed-off-by: Chris Evich <cevich@redhat.com>