remove CMDI envelope of xml center list

[dietuyt]

would it be possible for
​http://130.183.206.32/restxml/ not to have the CMDI part, so something like:

<Centers>

 <CenterProfile>
   <Centername>Eberhard Karls Universität Tübingen</Centername>
   <Center_id>1</Center_id>
   <Center_id_link>http://130.183.206.32/restxml/1</Center_id_link>
 </CenterProfile>

...
</Centers>

?

The reason is that we do not have a matching CMDI profile/XSD and that we do not need this information as CMDI file.

The CMDI formatting for the individual centers (e.g. ​http://130.183.206.32/restxml/5/) is ok and should stay like it is.