[API] New version of the prototype in Java

Hi,

I've just updated the API prototype in Java [1]. The major changes are:

+ We have explicit methods at the level of DDRPropertyValue for 
retrieving values of different types, including enumerations
+ I have included support for enumerations, thanks to the new created 
interface DDRValue which DDRPropertyValue inherits from

In an upcoming e-mail I will send a code snippet on how to use a 
PropertyValue that is enumerated

Best Regards

[1] http://www.w3.org/2005/MWI/DDWG/drafts/api/java/DDR-API-Minimal/doc/