[ZA] migrate to v2 of the PMG API

[mhl]

There's a new version of the PMG API available - @longhotsummer pointed out that an advantage of this is that we could selectively only return the fields we're using:

In addition, you may want to migrate to the V2 API, which allows you to specify field names to reduce response sizes:

https://api.pmg.org.za/v2/minister-questions/7411

eg: https://api.pmg.org.za/v2/minister-questions/7411?fields=year,date,intro

[longhotsummer]

Here are all the urls (take from https://github.com/OpenUpSA/pmg-cms-2/blob/master/pmg/api/v2.py):

/v2/committees/
/v2/committees/int:id
/v2/committees/int:id/meetings
/v2/committees/int:id/bills
/v2/committees/int:id/calls-for-comment
/v2/committees/int:id/tabled-reports
/v2/committees/int:id/members
/v2/committee-meetings/
/v2/committee-meetings/int:id
/v2/committee-meetings/int:id/attendance
/v2/minister-questions/
/v2/minister-questions/int:id
/v2/minister-questions/legacy/
/v2/minister-questions/legacy/int:id
/v2/ministers/
/v2/ministers/int:id
/v2/members/
/v2/members/int:id
/v2/calls-for-comments/
/v2/calls-for-comments/int:id
/v2/bills/
/v2/bills/int:id
/v2/daily-schedules/
/v2/daily-schedules/int:id