WebSsphere classpath patch [C2]

[Robert Marcano <ro...@promca.com>]

I made a few changes to the org.apache.cocoon.servlet.CocoonServlet in 
order to use the provided web application classpath.
WebSphere doesn't use the directory structure that exist inside a war 
file when it is imported (The servlet 2.2 spec does not enforce that the 
deployed jar must have the same directory structure), so Cocoon is not 
able to compile any classes.

WebSphere uses a ServletContext attribute called 
"com.ibm.websphere.servlet.application.classpath" that store the web 
application classpath. in order to be able to use it I added a new code 
to provide the name of this attribute using the servlet parameter named 
"classpath-attribute", if this attribute is defined this value will be 
used, if not the previous algorithm is used

hopes this helps