libvirt.tests: add new negative case into virsh domstate

Signed-off-by: Alex Jia <chuanchang.jia@gmail.com>
qemu_monitor_command: Add two more negative cases

Add a negative case for cover unknow cmd error, and another one
for invalid qmp command.

Signed-off-by: Wayne Sun <gsun@redhat.com>
Merge pull request #227 from chuanchang/add_cases_into_domstate

libvirt.tests: add new negative case into virsh domstate
Merge pull request #230 from waynesun09/qemu_monitor_cmd

qemu_monitor_command: Add two more negative cases
virsh.domstate: Add cases for on_crash action testing

Signed-off-by: Yanbing Du <ydu@redhat.com>