For weeks before NBC News journalists exploded into open revolt Sunday over the network’s hire of a top Donald Trump supporter‚ the media company that controls three of the top U.S. news networks had been quietly rebuilding its ties to the former president. Network insiders noticed on March 5‚ when‚ during MSNBC’s Super Tuesday broadcast of Trump’s primary wins‚ host Rachel Maddow indicated to producers off-camera that viewers had heard enough from the former president. MSNBC president...