Date formatting in excel export (line 5-24) to be added in main lib.

gistfile1.txt

						// if array changes, update it
						if ($arr !== $def_arr)
							$objPHPExcel->getActiveSheet()->fromArray($arr, NULL, "A2");
						
						// date formatting in excel 2007 +
						$excelCol = 'A';
						foreach($arr[0] as $k => $v)
						{
							if ($this->get_column($k,"formatter") == "date")
							{
								for($r=1;$r<count($arr);$r++)
								{			
									$date = $arr[$r][$k];
									$objPHPExcel->getActiveSheet()
										->setCellValue($excelCol.($r+2), PHPExcel_Shared_Date::PHPToExcel( $date ));
		
									$objPHPExcel->getActiveSheet()
										->getStyle($excelCol.($r+2))
										->getNumberFormat()
										->setFormatCode(PHPExcel_Style_NumberFormat::FORMAT_DATE_YYYYMMDD2);
								}
							}
							$excelCol++;
						}

						// write excel2007 standard xlsx
						$objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel2007');