Updated VOSI schema files

[Markus Demleitner]

Dear Giuila, 

(cc: GWS so they can protest if they disagree)

VOSI 1.1 (see https://volute.g-vo.org/svn/trunk/projects/grid/VOSI/)
has updated the VOSITables-v1.0.xsd schema -- there is now a tables
element, and you can tell you have the newer schema from the
@version="1.1" attribute in the root element.

For one reason or another, the update hasn't made it to the XML
schema page, http://ivoa.net/xml.  Could you update the file there?

The file name should not change -- I suppose we should archive the
old VOSITables-v1.0.xsd as VOSITables-v1.0-20110531.xsd (the document
date of VOSI 1.0) until we come up with a better scheme to accomodate
the new schema versioning policies
(http://ivoa.net/documents/Notes/XMLVers/index.html)

VOSIAvailability and VOSICapability are unchanged, so there's no need
to update them.

Thanks,

         Markus