Merge branch 'add/buster' into 'master'

Add buster build

See merge request !4
4 jobs for master in 7 minutes and 16 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Test Pre Build
passed #4396
test_build_script

00:01:22

 
  Build
passed #4397
build_nginx_buster

00:04:38

passed #4399
build_nginx_jessie

00:05:54

passed #4398
build_nginx_stretch

00:04:33