©Courtesy of 20th Century Studios The trailer for “Avatar: Fire and Ash” from Oscar-winning filmmaker James Cameron is here! The trailer and film stills are now available to download and share. The third film in the phenomenally successful “Avatar” franchise opens exclusively in theaters worldwide in IMAX 3D, Dolby Cinema 3D, RealD 3D, Cinemark XD, 4DX, ScreenX, and…