Merge branch 'add/debian-jessie' into 'master'

Add Debian Jessie build image

See merge request !6
10 jobs for master in 7 minutes and 18 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Test
passed #1949
lint-dockerfile

00:01:33

passed #1950
lint-shell-script

00:01:28

 
  Deploy
passed #1952
manual
build-debian-jessie-build-master

00:05:44

manual #1951
allowed to fail manual
build-golang-master
manual #1958
allowed to fail manual
build-php-5.3-master
manual #1957
allowed to fail manual
build-php-5.6-master
manual #1956
allowed to fail manual
build-php-7.0-master
manual #1955
allowed to fail manual
build-php-7.1-master
manual #1954
allowed to fail manual
build-php-7.2-master
manual #1953
allowed to fail manual
build-php-7.3-master