switching out for the new url

[binx]

closes #252

• [x] set up new route
• [x] set up redirect from /odes/extracts/
• [x] update tests

[migurski]

You're writing Python!

[binx]

I'm string-replacing in Python ;)

[migurski]

Still though. I will pick up some of the redirect stuff here.

[migurski]

Instead of redirects, I just made sure that the old links continue to work. New people will get the new ones.