Issues/912 members interests

Closes #912 (with caveat that data needs loading, and design probably needs doing)

- Adds an app for storing members' interests.
- Adds a command and JSON format for importing data
- Adds data provided to us regarding ZA politicians
- Adds script to convert this data into JSON format suitable for import.
- Adds 'Register of interests' section to the profile tab of the person detail page.

![joanmariae_louise_fubbs____pombola_south_africa](https://f.cloud.github.com/assets/187630/1665185/0b43365c-5c33-11e3-8c99-4fab4112a7ed.png)

Once merged:

- Run the commands added in 09d60de665bf40a6d7df50d9fb25d91b1b054197 to load the data on staging.
- Look at what design changes are needed.