ci: Add docker based test framework

* Add documentation
* Add .dockerignore: minimize docker context size to improve speed
* Add Makefile: to easily run various docker stages
* Add a CMake sample project to check CMake install rules

ci/docker/amd64/Dockerfile

@@ -0,0 +1,48 @@
+# Create a virtual environment with all tools installed
+# ref: https://hub.docker.com/_/ubuntu
+FROM ubuntu:latest AS env
+LABEL maintainer="corentinl@google.com"
+# Install system build dependencies
+ENV PATH=/usr/local/bin:$PATH
+RUN apt-get update -qq \
+&& DEBIAN_FRONTEND=noninteractive apt-get install -yq git wget libssl-dev build-essential \
+ ninja-build python3 pkgconf libglib2.0-dev \
+&& apt-get clean \
+&& rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+ENTRYPOINT ["/usr/bin/bash", "-c"]
+CMD ["/usr/bin/bash"]
+
+# Install CMake 3.21.3
+RUN wget "https://cmake.org/files/v3.21/cmake-3.21.3-linux-x86_64.sh" \
+&& chmod a+x cmake-3.21.3-linux-x86_64.sh \
+&& ./cmake-3.21.3-linux-x86_64.sh --prefix=/usr/local/ --skip-license \
+&& rm cmake-3.21.3-linux-x86_64.sh
+
+FROM env AS devel
+WORKDIR /home/project
+COPY . .
+
+FROM devel AS build
+RUN cmake -version
+RUN cmake -S. -Bbuild
+RUN cmake --build build --target all -v
+RUN cmake --build build --target install -v
+
+FROM build AS test
+ENV CTEST_OUTPUT_ON_FAILURE=1
+RUN cmake --build build --target test -v
+
+# Test install rules
+FROM env AS install_env
+COPY --from=build /usr/local /usr/local/
+
+FROM install_env AS install_devel
+WORKDIR /home/sample
+COPY ci/sample .
+
+FROM install_devel AS install_build
+RUN cmake -S. -Bbuild
+RUN cmake --build build --target all -v
+
+FROM install_build AS install_test
+RUN cmake --build build --target test