Add Bill URL for Divisions and Speeches

Bill subdebates include a unique ID that is used by ParlInfo to
tie speeches, the bill text and the bill digest together on a single
page which has a permanent URL. This patch adds this URL as an
attribute to speech major headings (which contain the Bill name used
for Public Whip) and divisions.
Make the indentation of both the `case` statements in this method the same as the rest of the code.