Implement magic accessors for RequestContext variables: you can now just call $contex...

Implement magic accessors for RequestContext variables: you can now just call $context->request->stuff(), and that is internally mapped to the get accessor.  Rename the private variables to the old $mName syntax: I know that that's "discouraged in new code", but in this case it stops over-clever IDEs highlighting the magic accesses as potential visibility errors and sticking big error tags on them.