In a memoir set to be published Tuesday, a former Facebook employee lays out allegations of misconduct at the company, including claims of sexual harassment and what she says were incomplete statements to Congress about Facebook’s relationship with China.Sarah Wynn-Williams says in the book and in an exclusive interview with NBC News that she faced retaliation from the company after she reported sexual harassment by her boss, Joel Kaplan, who at the time was a vice president for global public po...