add ST sequence

src/common/data/EscapeSequences.ts

@@ -119,6 +119,8 @@ export namespace C1 {
   export const DCS = '\x90';
   /** Private Use 1 */
   export const PU1 = '\x91';
+  /** String Terminator */
+  export const ST = '\x912';
   /** Private Use 2 */
   export const PU2 = '\x92';
   /** Set Transmit State */