Bug 24848: Improve manual links for the label creator

Bug 24848: Improve manual links for the label creator

Some of the manual links in the label creator tool were
not working correctly or pointing to the wrong pages.

A problem is the label-manage.pl file. This can show
different data depending on an added parameter. Example:
/cgi-bin/koha/labels/label-manage.pl?label_element=template

But it appears that parameters will be ignored when creating
links to the manual. So this patch links to the beginning
of the label creator section in the manual for now.

To test:
- Go to the lable creator
- Try the various pages of the tool
  - Note: All 'New ...' links should point to the
    correct section in the manual (batches, templates, ...)
    Except: Barcode range. This feature is new and not
    yet documented in the manual. Link goes to label creator section.
  - Note: All 'Manage ...' links should point to the
    beginning of the 'label creator' section in the manual

Signed-off-by: Andrew Fuerste-Henry <andrew@bywatersolutions.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>