Improved 9p sharing options in VM template

I'd like to propose an alternate interface for the "Unraid Share" 9p mounting options in the VM template.

The current method of picking a folder and providing a name:

can remain an advanced option, but I think what makes more sense in an Unraid world is to provide a list of shares and checkboxes. If you place a checkbox by the "Movies" share, it should be able to automatically map the source dir and target dirs in the template:

    <filesystem type='mount' accessmode='passthrough'>
      <source dir='/mnt/user/Movies/'/>
      <target dir='Movies'/>
      <address type='pci' domain='0x0000' bus='0x05' slot='0x00' function='0x0'/>
    </filesystem>

Similarly, when reading the template to build the form view it should be able to automatically figure out which source dirs and target dirs map to a Share and fill in the appropriate checkboxes on the form.