Warren Buffett has been buying up this consumer stock hand over fist, but the market keeps sticking to the sidelines.Pool Corp. (POOL +1.47%) is one of the latest stocks that legendary investor Warren Buffett has added to the portfolio of Berkshire Hathaway, his holding company. Yet while shares in this pool construction and maintenance products retailer has the Oracle of Omaha's "seal of approval," this has done little to spur bullishness on Wall Street.In fact, the share price tumbled by a third since the ...