NEW YORK (Reuters) - They are jumping ship or receiving the pink slip. America's real estate agents and mortgage lenders, that is. ADVERTISEMENT Now that the glory days of the most recent U.S. housing market are over, its deterioration is taking a toll on employees who profited from its record-breaking five-year run. With home sales slumping and loan demand diminishing, layoff announcements and resignations have become increasingly common, evidence that the sector's slump is broad. Carmen Cook, a veteran real estate broker, saw the writing on the wall and decided to retire earlier this year. "The market changed and my...