Reinstate missing regional_list function for members.
Replace legacy error code with exceptions.
Reinstate a paragraph to show where a member has changed parties.

Closes #441
Reinstate a list of previous constituencies represented by a member.
Add the entering and leaving parliament strings back to member profiles.
Merge branch 'mp-profile-history'
Replace house type integers with constants.
Merge branch '578-fix-msps'
Use &pound; instead of a UTF-8 £ sign
Fix for calling current_member as array instead of function.
Don't set the Cache-Control header on dev sites

Varnish observes the Cache-Control headers on our development server,
which is frustrating when you're actively changing the source and can't
see the changes when you reload the page.

This commit makes sure that TheyWorkForYou only emits Cache-Control
headers when DEVSITE is falsy.
Make configuration example aware of already defined constants.

Reduces the barrage of warnings during testing.
Update Composer and dependencies.
Merge branch 'reduce-test-noise'
Merge remote-tracking branch 'origin/no-cache-control-for-devsites'
Move to Codeception for testing.
Basic acceptance tests for key pages.
Move old PHPUnit tests to correct location for Codeception
First pass at installing Apache et al on Travis
Remove redundant phpunit.xml