[et-mgmt-tools] Virt-disk-path selection patch and other virt. attributes...

[Michael DeHaan]

I've checked in some modifications to the --virt-path code and 
rearranged it somewhat.

To use a standard disk image with koan:
    leave --virt-path off and assume defaults (like /var/lib/xen/images)
    or specify --virt-path=/path/to/directory
    or specify --virt-path=/path/to/directory/filename

To use an existing partition:
    specify --virt-path=/dev/sda4, or equivalent

To carve out of a chunk of a volume group, of the requested --virt-size, 
using the name cobbler would ordinarily choose:
    have an existing LVM volume group named something, such as 
VolGroup00, with some free space on it
    specify --virt-path=VolGroup00, or equivalent
    or be more specific:  --virt-path=VolGroup00 --virt-name=asdf   
(this creates /dev/mapper/VolGroup00/asdf)

Sidenote -- I've tested the above with qemu-kvm and they perform quite 
well.    When virt-manager's next-release supports installing these
via kickstart locations (like Xen), I'll move the kvm bits over to use 
virtinst -- until then, qemu-kvm systems created with koan do not show up
in virt-manager and you have to use the standard KVM tools for basic 
management.   That should change very shortly.

Additionally I've added a --virt-graphics flag to koan which enables VNC 
in both virt types ("qemu", "xenpv").    virt-graphics is currently not 
read as a default
value from cobbler, but it probably should be.  --virt-path and 
--virt-type can be passed to both koan and cobbler (profile add and 
system add).

--Michael