autotest/virt-test — pull request #307 by humanux (2013-04-22 08:08:22+00:00)
Title: qemu: Add macvtap support

This patch base pull request 303. in this version modify:
1. Act on one's recommendations， move code block of destroy macvtap to _cleanup().
2.modify the docstring of _cleanup function
Signed-off-by: Yunping Zheng