In between all the blockbusters and word-of-mouth hits of 2015, there are hidden gems. Films that deserved more attention than they got include Elijah Wood-produced thriller “The Boy,” Jemaine Clement”s take on vampires, and “Spring,” a genre-bending film with elements of both the “Before” trilogy and monster movies. These are HitFix”s picks for 2015 under the radar films well worth seeing.