** UK banks enjoy rally after Bank of England stress tests
** All Britain's main banks would be able to withstand asharp fall in house prices, other than the troubled Co-operativeBank, BoE says
** State-backed RBS & Lloyds both up around0.5 pct, with Barclays 1.5 pct higher & HSBC up 0.9 pct (RM: tricia.wright1.thomsonreuters.com@reuters.net)