SAO PAULO (Reuters) - Striking food inspectors who had slowed grain exports were ordered back to work by Brazil's attorney general on Friday as demand for soy and corn from Latin America's largest economy increased to head off a global food shortage. A union representing the inspectors said they would obey the court order, which came after soy and corn exporters turned to local courts to guarantee document clearance on Wednesday. Drought in the United States, the world's largest corn producer, has decimated corn and soy crops there. Brazil is the world's No. ...