Restrict xpath test so we get only the link we want

Adding a second link with the text "This version" broke the tests.
:'(
Use /dist/ links for SCO to get author-independent latest
Make "This version" test more specific for /pod, too

sigh.
Test the location header on the uc-author redirect
Move recent change log parsing to release controller

We don't need to do it for the pod controller.
Change Play Perl to Questhub

This should close #1120
Merge pull request #1135 from book/questhub

Change Play Perl to Questhub