'NOW 54' and 'NOW #1's' to be Released May 4; Available NOW for preorder LOS ANGELES, April 14, 2015 /PRNewswire/ -- The world's best-selling, multi-artist album series, NOW That's What I Call Music!, has gathered today's biggest hits for NOW That's What I Call Music! Vol. 54, to be released May 4. On the same date,…