The request stored in WebContext by the ContextFilter is never updated, and may miss parameters added by a forward.

For example, using a virtualUri filter in order to forward from /test/param.html to test..html?x=param I get different results when I do:
request.getParam("x") --> "param"
((WebContext) MgnlContext.getInstance()).getRequest().getParam("x") --> null

this also means that paragraphs never see parameters added by a forward, since the paragraph renderer gets the request from the context. Looks like a regression from 3.5, since I was using this kind of forwards and they stopped working after upgrading to 3.6 (not sure about which change in the filters has caused this).

I would propose to fix it by updating the request stored in WebContext any time ContextFilter processes the request. A good fix, without modifying in any way the WebContext interface, is doing something like the following:

        if (!MgnlContext.hasInstance() || MgnlContext.isSystemInstance())
        {
            MgnlContext.initAsWebContext(request, response, servletContext);
            contextSet = true;
        }
+        else
+        {
+            // update request
+            WebContext webContext = (WebContext) MgnlContext.getInstance();
+            webContext.init(request, response, servletContext);
+        }
+

I would like to commit this to 3.6.2, this can be a very annoying bug for anyone using forwards with parameters. Any objection?