fix bug 1045796 - remove/redirect links to derby
[bug 1045796] keep derby page, change derby content
fix bug 1045796 - pull down devderby

fix dupe listing on landing page

update previous challenges config value to include all previous challenges
update tests
Merge pull request #2665 from groovecoder/devderby-pulldown-1045796

fix bug 1045796 - remove devderby links