Add initial CI

This initial CI uses debian, ubuntu, fedora and opensuse docker images
to build bzip2.

.gitlab-ci.yml

@@ -0,0 +1,71 @@
+# CI setup based on https://gitlab.gnome.org/GNOME/librsvg/blob/master/.gitlab-ci.yml
+
+variables:
+  AMD64_DEBIAN_TESTING: debian:testing
+  AMD64_UBUNTU_BIONIC: ubuntu:bionic
+  AMD64_FEDORA_LATEST: fedora:latest
+  AMD64_FEDORA_RAWHIDE: fedora:rawhide
+  AMD64_OPENSUSE_LEAP: opensuse/leap
+  AMD64_OPENSUSE_TUMBLEWEED: opensuse/tumbleweed
+
+stages:
+  - test
+
+.test_bzip2_template: &bzip2_test
+  script:
+    - mkdir builddir && cd builddir
+    - ../autogen.sh
+    - make
+    - make check
+  after_script:
+    - cp builddir/config.status builddir/config.log .
+    - rm -rf builddir
+  artifacts:
+    paths:
+      - 'config.status'
+      - 'config.log'
+  
+debian:testing:
+  image: $AMD64_DEBIAN_TESTING
+  stage: test
+  before_script:
+    - apt update -y
+    - apt install -y gcc make automake libtool
+  <<: *bzip2_test
+
+ubuntu:bionic:
+  image: $AMD64_UBUNTU_BIONIC
+  stage: test
+  before_script:
+    - apt update -y
+    - apt install -y gcc make automake libtool
+  <<: *bzip2_test
+
+fedora:latest:
+  image: $AMD64_FEDORA_LATEST
+  stage: test
+  before_script:
+    - dnf install -y gcc make automake libtool
+  <<: *bzip2_test
+
+fedora:rawhide:
+  image: $AMD64_FEDORA_RAWHIDE
+  stage: test
+  before_script:
+    - dnf install -y gcc make automake libtool
+  allow_failure: true
+  <<: *bzip2_test
+
+opensuse/leap:
+  image: $AMD64_OPENSUSE_LEAP
+  stage: test
+  before_script:
+    - zypper install -y gcc make automake libtool
+  <<: *bzip2_test
+
+opensuse/tumbleweed:
+  image: $AMD64_OPENSUSE_TUMBLEWEED
+  stage: test
+  before_script:
+    - zypper install -y gcc make automake libtool
+  <<: *bzip2_test