If Grumpy Cat and “Keanu” haven’t sated your appetite for screen felines, try “A Street Cat Named Bob,” a savvy exercise in inspirational feel-good cinema lightly seasoned with grit. Adapted from James Bowen’s autobiography (part of a Bob franchise), the movie, directed by Roger Spottiswoode, tells how an orange cat enters the life of James (Luke Treadaway), a homeless London busker struggling with heroin addiction. Though James has a sobriety adviser (a firm Joanne Froggatt, as a persuasive living argument for public health care) who finds him housing, it is the cat, which James names Bob, who teaches him about responsibility and what it’s like to feel loved.