OWB-993 using a Proxy for TypeVariable as the interface has changed in Java8

Have to do this as it is  impossible to implement a TypeVariable which works with 
Java8 and Java7 at the same time 


git-svn-id: https://svn.apache.org/repos/asf/openwebbeans/trunk@1621271 13f79535-47bb-0310-9956-ffa450edef68