Nickelodeon has given the greenlight on more than 12 projects including “Sam & Cat,” a comedic spin-off show featuring the stars of “iCarly” and “Victorious” as teen entrepreneurs, “The Thundermans” about a family of superheroes, and “You Gotta See This” about the best of the web hosted by two of the stars from the network's show “How to Rock.” (THR)