Add MySQL stricton changes to mysqli and pdo/mysql drivers
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index d9c1a98..607388a 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -84,7 +84,7 @@
 	 *
 	 * @var	bool
 	 */
-	public $stricton = FALSE;
+	public $stricton;
 
 	// --------------------------------------------------------------------
 
@@ -153,19 +153,18 @@
 			{
 				$this->simple_query('SET SESSION sql_mode = CONCAT(@@sql_mode, ",", "STRICT_ALL_TABLES")');
 			}
-			else
+			elseif (version_compare($this->version, '5.7', '>='))
 			{
 				$this->simple_query(
 					'SET SESSION sql_mode =
-						REPLACE(
-							REPLACE(
-								REPLACE(@@sql_mode, "STRICT_ALL_TABLES,", ""),
-								",STRICT_ALL_TABLES",
-								""
-							),
-							"STRICT_ALL_TABLES",
-							""
-						)'
+					REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(
+					@@sql_mode,
+					"STRICT_ALL_TABLES,", ""),
+					",STRICT_ALL_TABLES", ""),
+					"STRICT_ALL_TABLES", ""),
+					"STRICT_TRANS_TABLES,", ""),
+					",STRICT_TRANS_TABLES", ""),
+					"STRICT_TRANS_TABLES", "")'
 				);
 			}
 		}