chore: remove dead links from humans.txt

Small PR, sorry for the noise!

I removed 3 dead links from humans.txt.

• https://www.ohloh.net/accounts/jonathanharker
• http://www.meldraweb.com/
• http://braawi.com/

The first 2 are just dead, the 3rd one technically isn't dead, it just takes you to a site with a bunch of NSFW content. ^-^'