View to edit a new request type.  Restricted to presidents and superadmins.
    Parameters:
        request is an HTTP request
        typeName is the request type's URL name.

def edit_request_type_view(request, typeName):
    ''' View to edit a new request type.  Restricted to presidents and superadmins.
    Parameters:
        request is an HTTP request
        typeName is the request type's URL name.
    '''
    requestType = get_object_or_404(RequestType, url_name=typeName)
    form = RequestTypeForm(
        request.POST or None,
        instance=requestType,
        )
    if form.is_valid():
        rtype = form.save()
        messages.add_message(request, messages.SUCCESS,
                             MESSAGES['REQUEST_TYPE_SAVED'].format(typeName=rtype.name))
        return HttpResponseRedirect(reverse('managers:manage_request_types'))
    return render_to_response('edit_request_type.html', {
        'page_name': "Admin - Edit Request Type",
        'request_types': RequestType.objects.all(),
        'form': form,
        'requestType': requestType,
        }, context_instance=RequestContext(request))