TEL AVIV, April 8 (Reuters) - Tens of thousands of Israelis joined protests on Saturday against Prime Minister Benjamin Netanyahu's plans to tighten controls on the Supreme Court, despite heightened security worries after two deadly attacks a day earlier. Netanyahu has mobilised border police reservists and ordered the army to reinforce security positions to head off possible trouble, amid calls for calm from the United Nations, the European Union and the United States. See here for a complete list of exchanges and delays