Bug 19849: Minor fixes & refactor of opac-reserve.tt & opac-user.tt

Bug 19849: Minor fixes & refactor of opac-reserve.tt & opac-user.tt

- make next patch easely reviewable.
- fix lone quote. (Replace by <strong>
- add forgotten condition for 9999-12-31

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 418eae24ccdb6b85b70cb302735770ce986c3593)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>