Merge branch...

Merge branch '96-update-contributors-guide-and-move-it-at-top-level-so-it-s-recognised-by-gitlab' into 'master'

Update contributor's guide and move it to top level, so it's recognized by GitLab

Closes #96

See merge request !58
4 jobs for 120-bind-9-11-addzone-fails in 11 minutes and 25 seconds (queued for 7 seconds)
Status Job ID Name Coverage
  Build
passed #2627
linux docker
build:debian:sid:amd64

00:05:06

passed #2628
linux docker
build:debian:sid:i386

00:05:31

 
  Test
passed #2629
linux docker
test:debian:sid:amd64

00:05:50

passed #2630
linux docker
test:debian:sid:i386

00:05:53