Update MP Page Template

A large overhaul of the MP pages, including how they are assembled behind the scenes.

* Closes #399.


Deal breakers

The following are parts of MP pages which need migrating.
* [x] Special message about Sinn Fein MPs (any other lost special cases?)
* [x] Test for above
* [x] MP photo
* [x] Test for above
* [x] Remove link to non-existant votes page



## MP Page parts
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* [x] Name
* [x] Image
* [x] Constituency
* [ ] Date of joining/leaving (whichever bodies over their history)
* [x] Previous constituencies held (or similar)
* [ ] Party changes
* [x] Alert Subscription Button
* [x] WTT Button
* [x] Voting Record
* [x] Rebellion Rate
* [x] Recent Appearances
* [x] RSS Links
* [x] Numerology
* [x] Register of Interests
* [x] Member Summary String
* [x] Previous Constituency MPs
* [x] Future Constituency MPs
* [x] Topics of Interest
* [ ] Chairman's panel information
* [x] Public Bill Committees
* [x] Expenses
* [x] Useful Links
* [x] Previous Positions
* [ ] Note for Journalists
* [ ] No photo message

## Design Love

The following sections could do with a bit more design love before launch.

* [ ] Voting Record (needs rebellion indicator, better list styling)
* [ ] Left/right page margin at medium widths

* [x] Very long names in Lords
* [ ] Background images for different assemblies
* [x] Member's interests
* [x] Profile

## Tests

* [ ] Basic loading of MP page has things on it appropriately.
* [ ] Lord
* [x] MLA
* [ ] MSP
* [x] Speaker
* [x] The Queen
* [ ] Loading a Sinn Fein MP page - special message, no email alert/voting record
* [ ] Unless they're also an MLA, in which case special message, but yes email alert...
* [ ] Other stable tests - join/leaving date of retired MP, previous offices, party, voting record is present.