map TechTV routes for videos that have migrated to YouTube

[pdpinch]

For some TechTV videos, we can determine if they have been permanently moved to YouTube. For these videos, we would like to direct users immediately to YouTube.

Proposal:

• [ ] Collection pages return 301 redirect to YouTube channel page
• [ ] Video detail pages return 301 redirect to YouTube video watch page
• [ ] Embed URLs return YouTube embed page
• [ ] Allow enough flexibility that we're not bound only to YouTube. I.e. if a video moved to Vimeo, we'd still like to be able to redirect

Requirements:

• [ ] model for storing necessary mappings of collections
• [ ] @emmello will need to collect URLs

[pdpinch]

We've decided to just stream from YouTube instead of doing a redirect.