Nikkei rises slightly, insurers gain on higher bond yields
TOKYO, June 4 (Reuters) - Japan's Nikkei share average eked out its first gains in three sessions on Thursday, with insurers leading the way on higher Japanese and global bond yields, though rising volatility in bond prices kept many investors cautious. The Nikkei 225 rose 0.1 percent to 20,488.19, **t far from its 15-year high of 20,655.33 hit a week ago. Online retailer Rakuten dived 6.2 percent on its plan to issue new shares to raise about 188 billion yen ($1.5 billion) and to use 90