Some folks in the Twitterverse apparently don’t know their musical history. Angry Twitter users took to the social media platform in the days leading up to NBC’s broadcast of “The Wiz Live!†to decry what they considered racist casting. The Thursday-night live production featured an all-black cast led by Queen Latifah, David Alan Grier, Ne-Yo and newcomer Shanice Williams. That is in keeping with the history of the stage musical, which has always featured a black cast, as well as the 1978 film starring Diana Ross and Michael Jackson. However, many Twitter users vented about the casting nonetheless. I just...