Import Zuul unittests

Add the unittests in-tree and convert them as Zuul v3 native tests so
that they can be modified locally.

This adds a new job running on Ubuntu and an experimental CentOS-7 one.

Change-Id: Ib43e40280411623fda84f2068958b64a17cdc3dc

.zuul.yaml

@@ -0,0 +1,25 @@
+- job:
+    name: liberasurecode-unittests
+    parent: unittests
+    description: |
+      Build and run test and valgrind-test for liberasurecode.
+    run: playbooks/unittests/run.yaml
+
+- job:
+    name: liberasurecode-unittests-centos-7
+    parent: liberasurecode-unittests
+    nodeset: centos-7
+    description: |
+      Build and run test and valgrind-test for liberasurecode.
+      This job runs on CentOS-7.
+
+- project:
+    check:
+      jobs:
+        - liberasurecode-unittests
+    gate:
+      jobs:
+        - liberasurecode-unittests
+    experimental:
+      jobs:
+        - liberasurecode-unittests-centos-7

playbooks/unittests/run.yaml

@@ -0,0 +1,15 @@
+- hosts: all
+
+  tasks:
+    - name: Build and test
+      shell:
+        cmd: |
+          set -e
+          set -x
+          ./autogen.sh
+          ./configure
+          make
+          make test
+          make valgrind-test
+        executable: /bin/bash
+        chdir: '{{ zuul.project.src_dir }}'