[simple-scan] Build CI on three OSs, fix build instructions

[Robert Ancell <rancell src gnome org>]

commit 4bd6744d59ec5ba49b222e548ffdec0165f873fd
Author: Robert Ancell <robert ancell canonical com>
Date:   Thu Dec 7 10:29:40 2017 +1300

    Build CI on three OSs, fix build instructions

 .gitlab-ci.yml | 31 ++++++++++++++++++++++++-------
 1 file changed, 24 insertions(+), 7 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 71aa230..6d30faa 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,14 +1,31 @@
-image: ubuntu:16.04
-
 stages:
  - build
 
-before_script:
-  - apt-get update
-  - apt-get install -q -y meson valac libgtk-3-dev libgusb-dev libcolord-dev libpackagekit-glib2-dev 
libwebp-dev libsane-dev gettext itstool
+build-ubuntu-lts:
+  image: ubuntu:16.04
+  stage: build
+  before_script:
+    - apt-get update
+    - apt-get install -q -y meson valac gettext itstool libgtk-3-dev libgusb-dev libcolord-dev 
libpackagekit-glib2-dev libwebp-dev libsane-dev
+  script:
+    - meson _build
+    - ninja -C _build install
+
+build-ubuntu-latest:
+  image: ubuntu:17.10
+  stage: build
+  before_script:
+    - apt-get update
+    - apt-get install -q -y meson valac gettext itstool libgtk-3-dev libgusb-dev libcolord-dev 
libpackagekit-glib2-dev libwebp-dev libsane-dev
+  script:
+    - meson _build
+    - ninja -C _build install
 
-build-simple-scan:
+build-fedora:
+  image: fedora:27
   stage: build
+  before_script:
+    - dnf install -y meson valac gettext itstool gtk3-devel libgusb-devel colord-devel 
PackageKit-glib2-devel libwebp-devel sane-backends-devel
   script:
-    - meson _build .
+    - meson _build
     - ninja -C _build install