* Forty nations discuss Syrian refugee crisis in Berlin * Syria's neighbours speak of huge and unequal burden * Jordanian minister warns of tension with host communities (Adds German, Turkish and Lebanese ministers, background) By Stephen Brown BERLIN, Oct 28 (Reuters) - Syria's neighbours are approaching "host-country fatigue" because of huge demand from refugees for housing, schools, jobs and healthcare and scant resources like water, Jordan's foreign minister said on Tuesday. Leba**n and Turkey echoed that message at an international conference in Berlin on what U.N. ...