New Doc: JPA Concepts

[David Blevins]

In an effort to apply some clarity and sanity to the world of JPA,  
I've whipped up this document that attempts to put in all into  
perspective.

 http://cwiki.apache.org/OPENEJBx30/jpa-concepts.html
 (will synch to http://openejb.apache.org/3.0/jpa-concepts.html soon)
Great read for anyone.  If you like it feel free encouraged send back  
a "thanks" :)

-David