downgrade cmake req. to 3.5

.travis.yml

@@ -0,0 +1,13 @@
+sudo: required
+
+services:
+  - docker
+
+install: |
+  docker build -t neopg-build-env prov
+
+script: |
+  docker run \
+    --name neopg-build-env \
+    --rm neopg-build-env \
+    sh -c "git clone https://github.com/lambdafu/neopg.git && cd neopg/build && git checkout $TRAVIS_COMMIT && git submodule update --init && cmake -DCMAKE_BUILD_TYPE=Debug .. && cmake --build . && make test && make coverage"

CMakeLists.txt

@@ -3,7 +3,7 @@
 #
 # NeoPG is released under the Simplified BSD License (see license.txt)
 
-cmake_minimum_required(VERSION 3.8 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.5 FATAL_ERROR)
 project(NeoPG VERSION 0.1 LANGUAGES C CXX)
 
 # Google Test

prov/Dockerfile

@@ -0,0 +1,39 @@
+FROM ubuntu
+
+# dependencies
+RUN apt-get update && apt-get install -y \
+    build-essential \
+    cmake \
+		libsqlite3-dev \
+		libbotan1.10-dev \
+		libz-dev \
+		bzip2 \
+		gcovr \
+		cppcheck \
+		doxygen \
+		lcov \
+		git \
+		libboost1.58 \
+		pkg-config \
+		libusb-1.0-0-dev \
+		libbz2-dev \
+		libgnutls-dev \
+		git \
+	&& rm -rf /var/lib/apt/lists/*
+
+# build botan
+RUN git clone https://github.com/randombit/botan.git
+RUN cd botan \
+	&& git checkout 2.3.0 \
+	&& ./configure.py \
+	&& make install
+
+ENV GIT_COMMIT=master
+#ENTRYPOINT git clone https://github.com/lambdafu/neopg.git \
+#	&& cd neopg \
+#	&& git checkout $GIT_COMMIT \
+#	&& cd build \
+#	&& cmake -DCMAKE_BUILD_TYPE=Debug .. \
+#	&& cmake --build \
+#	&& make test
+##tail -F /var/log/messages