ZA: improve linking between SayIt speakers and Pombola persons

[geoffkilpin]

The current approach to linking is limited:

• The url for a speaker in a speech view is (e.g.) http://www.pa.org.za/speaker/m-shinn, which is then redirected by SASpeakerRedirectView to http://www.pa.org.za/person/marian-robin-shinn/.

  Aside from being a bit slow, this results in a number of 404 errors. If we have not matched a speaker to a person we shouldn't be displaying a link.

  It also results in speeches by speakers with titles (the President, Leader of the Opposition, Speaker, ministers etc.) not matching - e.g. http://www.pa.org.za/speaker/minister-of-telecommunications-and-postal-servic-2. (previously noted in Hansard parsing issues #1270).

• Most SayIt speeches appear to be assigned to a SayIt speaker linked to a PopIt person. As far as I can tell there is no database relationship between a PopIt person and a Pombola person, which would require making the connection using identifiers and complicating the process of getting an absolute person url or retrieving a person's party.

• When making connections between SayIt speakers and PopIt persons, get_person does not consider positions (for ministers, the speaker, etc.) nor does it take into account whether the person matched was a member of the relevant organisation at the time of the speech (the A J Williams example noted in Hansard parsing issues #1270).

  When the speech was made is naturally important for position matches so that a ministerial reply or speech by the speaker is assigned to the correct person.