Adding extra team / alumni members

Thanks to @dchelimsky for point out missing people, I'll add them here, still need to add a few more.

Team:
- [ ] @yujinakayama 

Alumni:
- [ ] Dave Astels
- [ ] Aslak Hellesøy
- [ ] Chad Humphries
- [ ] Pat Maddox
- [ ] Luke Redpath
- [ ] Justin Ko
Maybe I misunderstood, I took "taking a break" to mean he was stepping down from the team for a while, if he comes back we can easily put him in the team section :)