[webgui] let specify extra arguments for http server used
[webgui] let specify extra arguments for http server used

Some special features may not be covered by regular WebGui parameters

olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root