Pegasystems Inc. (Nasdaq:PEGA) stock soared 18.4 percent in after hours trading after the software company reported Q4 results that beat analyst expectations. The now Cambridge, Mass.-based provider of customer relationship management products said revenue for the fourth quarter of 2012 rose 25 percent compared to the same quarter 2011. Net income was $20.4 million or 53 cents per share, compared to a net loss of $1.9 million or (5 cents) per share for the same period 2011. Pegasystems reported…