0.6.0

Lot's of space savings in this release!

Details

1. rebase onto latest master
2. split up gcc libs into different outputs to save a bunch of space ~500MB
3. strip all binaries and libraries more aggressively
4. restructure images to make more sense
5. do not install all firmware anymore, just the ones we need
6. remove sotruss from glibc
7. disable more services in the mini (previously minimal) image
8. add experimental micro image