virt: Add os_variant to guest-os configs

Libvirt uses the combination of os_type and os_variant
to help determine guest machine_type (and other parameters).
However it cannot do this if the os_variant information is
not provided.

* Updated All Fedora/RHEL/OpenSUSE/JeOS/Ubuntu/SLES guest
  definitions with their proper os_variant.

* Modified the default libvirt tests.cfg filter to make
  use of os_variant param during unattended install.

Signed-off-by: Chris Evich <cevich@redhat.com>
virt-libvirt: Serial-console output same as qemu-kvm

libvirt VM class should log serial_console output to same
place as qemu-kvm.  Added methods to help set this up
and help with cleanup in key places.

Signed-off-by: Chris Evich <cevich@redhat.com>
virt: Use zero-based serial device names (Params)

libvirt automatically creates a device alias for serial devices
starting with 'serial0'.  However, base.cfg defaults to
counting from serial1.  In order for this name to be used
by unattended_install in the same way for libvirt and qemu,
the device naming must be consistent.  This will allow us to
use a common interface in unattended_install.

Signed-off-by: Chris Evich <cevich@redhat.com>
virt: Update serial console handling in unattended install

use the same completion signal (serial console log file)
for both qemu-kvm and libvirt.  This depends on zero-based
naming of serial devices, since the name is used in libvirt
to locate the actual guest-device.  Then the same log-file
name can be used for both qemu-kvm and libvirt tests.

Signed-off-by: Chris Evich <cevich@redhat.com>
virt: Update .gitignore for guthub tool cache

An upcoming revision of the github tool will use
a caching directory.  Just ignore anything with
cache in it's name.

Signed-off-by: Chris Evich <cevich@redhat.com>
virt: Ignore 10 unattended_install serial log errors

Previously it was possible due to timing, for the test
to clobber the vm's serial log file, then monitor
the wrong file.  This patch makes it ignore the first
ten attempts to read the file, then it starts making noise.
There's no need I'm aware of why the test should have
to ever create the log file, it just needs to be more
patient.

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