Bug 6547: Add id attributes to messages in opac-reserve.tt

Bug 6547: Add id attributes to messages in opac-reserve.tt

In order to allow easier styling with JQuery, including text substitution,
this patch adds id attributes to each div tag containing a holds message.
The following ids are added, corresponding to the template variables of the
same names:

too_much_oweing
too_many_reserves
bad_biblionumber
no_items_selected
no_branch_selected
no_biblionumber
bad_data
none_available

Signed-off-by: Nicole C. Engard <nengard@bywatersolutions.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>