Correct metadata in vSphere OVA generation

There are some superfluous element definitions in the vSphere
OVA metadata. These include the IDE disk and Video Card
definitions.

Additionally, there are some superfluous definitions which break
backward compatibility with vSphere 4. These include the vmw:Config
element definitions under the heading '#configs'.

Finally, some of the 'Item' elements are numbered non-sequentially.
Fixed that.