A version of this article first appeared in CNBC's Inside Wealth newsletter with Robert Frank, a weekly guide to the high-net-worth investor and consumer. Sign up to receive future editions, straight to your inbox.The top 10% of Americans added $5 trillion to their wealth in the second quarter as the stock market rally continued to benefit the biggest investors, according to new data from the Federal Reserve.The total wealth of the top 10% — or those with a net worth of more than $2 million — re...