Fixed an incorrect stack comment where an "a" just vanished (thanks /u/bagtowneast)

README.md

@@ -1919,7 +1919,7 @@ but ours isn't, so we are fine.
            AND,                 /* ( n a old-highbyte )   r: ( caller )   */
            SWP, TOR,            /* ( n old-highbyte )     r: ( caller a ) */
            OR,                  /* ( new-n )              r: ( caller a ) */
-           RTO,                 /* ( new-n )              r: ( caller )   */
+           RTO,                 /* ( new-n a )            r: ( caller )   */
            ST,                  /* ( )                    r: ( caller )   */
            RET);
 ```

frustration.rs

@@ -1816,7 +1816,7 @@ fn build_dictionary(c: &mut Core) {
            AND,                 /* ( n a old-highbyte )   r: ( caller )   */
            SWP, TOR,            /* ( n old-highbyte )     r: ( caller a ) */
            OR,                  /* ( new-n )              r: ( caller a ) */
-           RTO,                 /* ( new-n )              r: ( caller )   */
+           RTO,                 /* ( new-n a )            r: ( caller )   */
            ST,                  /* ( )                    r: ( caller )   */
            RET);