(print-diary-entries-hook, diary-list-entries): Doc fixes.

(print-diary-entries-hook, diary-list-entries): Doc fixes.
(abbreviated-calendar-year): Move here from calendar.el.  Doc fix.
(diary-header-line-flag, diary-header-line-format): Declare.
(diary-pull-attrs): Check for multiple matches.
(diary-list-entries-2): Simplify finding start of date.
(diary-show-all-entries, make-diary-entry): Respect non-nil values of
pop-up-frames.
(diary-mark-entries-1): Re-use offset in abbreviated-year case.
(mark-sexp-diary-entries): Remove superfluous call to diary-pull-attrs.