[lmi] Group quotes: empty footnotes

[Greg Chicares]

First of all, this is not needed before Halloween, and I'd rather not
even discuss it until after the release. We will produce group quotes
for two product families: one regulated by the fifty states only, and
the other regulated by the federal government as well as the states.
They have different footnote requirements:

    footer_           =
                          escape_for_html_elem(ledger.GroupQuoteIsNotAnOffer   )
        + "<br><br>"    + escape_for_html_elem(ledger.GroupQuoteRidersFooter   )
        + "<br><br>"    + escape_for_html_elem(ledger.GroupQuotePolicyFormId   )
        + "<br><br>"    + escape_for_html_elem(ledger.GroupQuoteStateVariations)
        + "<br><br>"    + escape_for_html_elem(ledger.MarketingNameFootnote    )
[above: state regulation--all products]
[below: federal regulation--some products]
        + "<br><br><b>" + escape_for_html_elem(ledger.GroupQuoteProspectus     
) + "</b>"
        + "<br><br>"    + escape_for_html_elem(ledger.GroupQuoteUnderwriter    )
        + "<br><br>"    + escape_for_html_elem(ledger.GroupQuoteBrokerDealer   )
        ;

We laid it out that way so that the two families' PDF files are pretty
much indistinguishable except for the extra footnotes at the end. For
the first family (state regulation only), the last three footnotes are
present but invisible, because they're empty strings. Their associated
<br> line breaks are also unconditionally present, simply because I
didn't put enough thought into the design when I added them.

A problem arises if, in the future, we rearrange footnotes. Suppose
we move the second one to the end. Then the PDF has an unsightly gap
due to the unconditional <br><br>, and we'd like to eliminate that gap.
I.e., if a footnote is an empty string, then its <br><br> should not be
written at all. (The criterion really is string::empty(); we will not
specify any all-blank strings.)

Vadim, would you please put this aside for a couple weeks at least,
and then propose a patch?