Developed some of the content on the index page.  Explained that JEXL is not compatible with JSTL EL but that it is inspired by JSTL, JSP, and Velocity.  Also added a setup paragraph for the code example.
Developed some of the content on the index page.  Explained that JEXL
is not compatible with JSTL EL but that it is inspired by JSTL, JSP, and
Velocity.  Also added a setup paragraph for the code example.


git-svn-id: de0229a90a04588cc4459530912ec55932f3d65c@136579 13f79535-47bb-0310-9956-ffa450edef68

apache/commons-jexl,apache/commons-jexl,apache/commons-jexl