Better handling of subsite redirects

[chaselgrove]

Currently subdomain redirects are done by a UMass-managed server. These should be handled by ReproNim.

Redirects are:

• 5steps.repronim.org: https://www.repronim.org/5steps.html
• brainverse.repronim.org: https://github.com/repronim/brainverse
• courses.repronim.org: https://courses.repronim.org/
• neuroblast.repronim.org: http://www.repronim.org/
• niceman.repronim.org: https://github.com/repronim/reproman
• reproin.repronim.org: https://reproin.repronim.org/
• reproman.repronim.org: https://github.com/repronim/reproman
• training.repronim.org: https://www.repronim.org/teach.html

In addition, reproducibleimaging.org (and subdomains under it) are redirected to repronim.org.

[memartone]

Discussion by Austin, Dave and Christian. Other than 5 steps, most of these are not mission critical at this point. And most don't affect the current website.