virt-test: Add '--qemu-dst-bin'

Add --qemu-dst-bin to allow the destination binary of a migration
to be specified separately from the source, allowing cross-version
compatibility testing.

Changes from v1:
 * Avoid setting dst binary if None passed
 * Don't try too hard to find one, as we do with qemu_bin

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
requirements.txt: Cleanups

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
tools: Remove check_patch and other auxiliary scripts

As they've been replaced by inspekt.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
virttest.staging.backports.simplejson: Supress E0111 message

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
documentation: .rst fixes

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
virttest: Docstring fixes

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge pull request #1615 from autotest/docs-2

Mass docstring and .rst documentation fixes
Merge pull request #1604 from autotest/dgilbert

virt-test: Add '--qemu-dst-bin'