Update be-9999.ebuild for DocBook 5 man page generation.

Update be-9999.ebuild for DocBook 5 man page generation.

From the BE repository:

commit 8c9f876ae69f7bf92686edea320931d875b5c681
Author: W. Trevor King <wking@drexel.edu>
Date:   Tue Sep 28 21:25:43 2010 -0400

    Converted man page source to DocBook V5.0.

    This has the dual benefits of keeping up with the current DocBook
    standard as well as removing the dependency on SGML parsers like
    docbook-to-man and docbook2man which may not be available on all
    systems.  An XSLT processor and the DocBook style sheets are easier
    dependencies to satisfy.