Add sequences in Standard libraries

[ydah]

see: https://gitlab.inria.fr/fpottier/menhir/blob/master/src/standard.mly#L182-205

/*
 * program: preceded(opening, X)
 *
 * =>
 *
 * program: preceded_opening_X
 * preceded_opening_X: opening X
 */
%rule preceded(opening, X): opening X { $$ = $2; }
                          ;

/*
 * program: terminated(X, closing)
 *
 * =>
 *
 * program: terminated_X_closing
 * terminated_X_closing: X closing
 */
%rule terminated(X, closing): X closing { $$ = $1; }
                            ;

/*
 * program: delimited(opening, X, closing)
 *
 * =>
 *
 * program: delimited_opening_X_closing
 * delimited_opening_X_closing: opening X closing
 */
%rule delimited(opening, X, closing): opening X closing { $$ = $2; }
                                     ;

[yui-knk]

Once %inline is supported, let's consider to change these rules to be %inline because they are defined as %inline in Menhir.