The Internet of 2010 contained many things, and free of charge. It had the full works of Shakespeare. It had robust English translations of classical Greek philosophy. It had just about every Miley Cyrus lyric. But when Joshua Foer, author of “Moonwalking With Einstein” and creator of the travel website Atlas Obscura, sat down one day to find a modern, complete English translation online of the Talmud, or Jewish Oral Law, he came up mostly empty, save for some pirated PDFs and a host of anti-Semitic sites.