There's not a whole lot that's new about "The Hitman's Bodyguard ." Its mismatched-pals premise is the stuff of classic buddy comedies. Stars Ryan Reynolds and Samuel L. Jackson play their typical character types: Reynolds the handsome do-gooder; Jackson the unflappable badass whose favorite word is mother(expletive). And like many movie heroes past, they're tasked with taking down a brutal dictator....