* Abu Dhabi’s Aldar gains on foreign property ownership plan * FAB rises after foreign ownership limit hike * 10 of 12 Saudi banks slide * Qatar’s QISB, Commercial Bank climb on higher Q1 profit By Shakeel Ahmad April 18 (Reuters) – Abu Dhabi’s stock market rose sharply on Thursday to reach its highest level in more than 13 years, partly lifted by top lender First Abu Dhabi Bank which has gained this week after regulatory approval to raise foreign ownership limit of its shares. The Abu Dhabi index rose 1.1 percent to its highest since December 2005 with First Abu Dhabi Bank increasing 1.5 percent. The bank has risen nearly 9 percent this week after obtaining regulatory approval last week to increase its