By Richard Cowan and Andy Sullivan WASHINGTON (Reuters) -Bipartisan negotiations in the U.S. Senate on gun control legislation, which follow massacres at a Texas elementary school and a Buffalo, New York, supermarket last month, will continue amid some signs of progress, Senate Majority Leader Chuck Schumer said on Tuesday. “Senator (Chris) Murphy has asked for some space to have the bipartisan talks continue, and I have given him that space. I look forward to discussing the status of those talks with my colleagues today,” Schumer — who, like Murphy, is a Democrat — said on the Senate floor….