Merge branch 'add/buster' into 'master'

Add buster build

See merge request !4
4 jobs for master in 7 minutes and 6 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Test Pre Build
passed #7169
test_build_script

00:01:14

 
  Build
passed #7170
build_nginx_buster

00:03:46

passed #7172
build_nginx_jessie

00:04:54

passed #7171
build_nginx_stretch

00:05:52