LONDON (Reuters) - British house prices perked up in March and rose in London at their fastest pace since December 2016 before the market effectively shut down in April due to the coronavirus lockdown, official figures showed on Wednesday.Average house prices across the United Kingdom increased by 2.1%, up from 2.0% in February, their joint-fastest rise since November 2018, while house prices in London alone increased by 4.7%, the Office for National Statistics said.The ONS has said it will not..