Shelter, the UK’s leading housing and homelessness charity, is calling on Londoners to come together this Christmas and Sleep Walk for Shelter in order to raise money to support the 135 families across Britain who become homeless every day. Sleep Walk for Shelter is a 10-kilometre night walk through London where supporters will come together to brave the winter elements, and make a stand against homelessness this Christmas. The walk will start in Liverpool Street and end in Waterloo, where participants will come…