Borrower notification templates are not easily extensible

[aw-bib]

Basically, due to load_template() implementation in bibcirculationadminlib it is currently not possible to add additional borrower notification forms without changing invenio core code. As the templates available are configured via the CFG_BIBCIRCULATION_TEMPLATES-dictionary, it seems reasonable to allow all keys in this very dict as valid templates.

Thus, the minimal invasive, invisible, change to the code would be to add a further elif statement checking if value passed is a key in the dict and if so just load the template associated. If one wants to restrict templates displayed to the librarian one could then move this kind of config to the bibcirculation_template_<CFG_WEBSTYLE_TEMPLATE_SKIN> for the generation of the associated select-box in html.

isRequiredFor: join2/join2#1066, join2/join2-data#2011