Reuters Quote: US STOCKS-Wall St opens mixed ahead of homebuilder
* Endo down after agreeing to buy Par Pharmaceutical * Altera up on report of possible deal with Intel * Ann rises after Ascena Retail takeover offer * S&P closed at record-high on Friday * Indexes: Dow up 0.05 pct, S&P down 0.02 pct, Nasdaq down 0.08 pct (Updates to open) By Sweta Singh May…