Update "First Hops" Documentation

The "First Hops" portion of the Apache Jackrabbit site is out of date.

http://jackrabbit.apache.org/doc/firststeps.html

It still references Jackrabbit 1.0 - and the project is onto release 1.3; it also references several dependencies - and the downloads page is no longer clear as to which jar files would be required to get a basic repository application up and running.