Bug 10354 - Don't show optgroup Libraries when no search groups are defined

In the OPAC, if there are no search groups defined, there's no reason to
embed library choices inside an <optgroup>. <optgroup> should only be
used to differentiate the list of individual libraries from search
groups. This patch removes the <optgroup> when no search groups are
enabled.

To test, apply the patch and:

- Enable OpacAddMastheadLibraryPulldown.
- Create a library search group in Administration ->
  Libraries and Groups and enable it by checking the "show in search
  pulldown" box.
- View the library pulldown in the OPAC search bar. Libraries and groups
  should be separated into <optgroup>s.
- Disable your library search group and refresh the OPAC page. The
  pulldown of libraries should now display libraries with no <optgroup>.

Signed-off-by: Srdjan <srdjan@catalyst.net.nz>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>

koha-tmpl/opac-tmpl/prog/en/includes/masthead.inc

@@ -87,13 +87,13 @@
    [% IF ( OpacAddMastheadLibraryPulldown ) %]
       <select name="branch_group_limit" id="select_library" class="left">
          <option value="">All libraries</option>
-         <optgroup label="Libraries">
+         [% IF BranchCategoriesLoop %]<optgroup label="Libraries">[% END %]
              [% FOREACH BranchesLoo IN BranchesLoop %]
                 [% IF ( BranchesLoo.selected ) %]<option selected="selected" value="branch:[% BranchesLoo.value %]">[% BranchesLoo.branchname %]</option>
                 [% ELSE %]<option value="branch:[% BranchesLoo.value %]">[% BranchesLoo.branchname %]</option>[% END %]
              [% END %]
-         </optgroup>
          [% IF BranchCategoriesLoop %]
+             </optgroup>
              <optgroup label="Groups">
                  [% FOREACH bc IN BranchCategoriesLoop %]
                      [% IF ( bc.selected ) %]