Merge branch '16-return-json-instead-of-plain-text' into 'master'

Resolve "Return json instead of plain text"

Closes #16

See merge request !11
4 jobs for 17-only-test-a-ip-address-once in 1 minute and 11 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #68272
docker linux
build:centos:centos7:amd64

00:00:31

passed #68273
docker linux
build:debian:sid:amd64

00:00:33

 
  Test
passed #68274
docker linux
test:centos:centos7:amd64

00:00:36

passed #68275
docker linux
test:debian:sid:amd64

00:00:37