Temporarily broke the build on the JDK7 branch

[Martin Desruisseaux]

Hello all

In contradiction with what I just told today in an earlier email, I have 
intentionally and temporarily broken the build on the JDK7 branch. 
Porting the metadata implementations will take me one more day, but I 
preferred to commit what has been done today (JAXB adapters) for safety. 
This is about 90 classes, which is about half of the planed commit. The 
build will be restored when I will commit the other half tomorrow.

Other branches and the trunk are not affected.

    Martin