[webgui] create dummy directory as firefox profile
[webgui] create dummy directory as firefox profile

Firefox has bug that profile creation fails if there is no Internet
connection. But dummy empty directory works as well as Firefox profile
olifre/root,root-mirror/root,olifre/root,root-mirror/root,karies/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,karies/root,olifre/root,root-mirror/root,karies/root,olifre/root,olifre/root,root-mirror/root,karies/root,olifre/root,root-mirror/root,karies/root,root-mirror/root,root-mirror/root,karies/root,olifre/root,olifre/root,karies/root,karies/root,karies/root,karies/root,root-mirror/root,olifre/root,olifre/root,karies/root