Support for Windows Guest (cfg changes, and modification of vdagent and copyandpaste tests)

Support for Windows Guests
tests-spice.cfg: updates to support windows guest tests
rv_setup: updates to install qxl, virtio, and vdagent for a windows guest
vdagent.py: win guest support added
copyandpaste.py: adding win guest support
utils_spice.py: some of the common utils are updated to handle either rhel or windows os.

minor updates as needed to other files.