Util.toCapital:  respect <span class="nocase">.
Pandoc:  Capitalize first word of citation note, unless span=nocase.

Previously we only capitalized citations.  This captures ibid
and the like.
Removed ibid-c, ibid-with-locator-c.

We now just use ibid, ibid-with-locator.  The earlier code
erroneously capitalized the first ibid. in a citation, even if
it was in the middle of a sentence.

Closes #68.