Fix pip install in unit test container

The SWIG_FEATURES environment variable is to get pip install working with M2Crypto==0.22.3. It works without SWIG_FEATURES if we update to M2Crypto >= 0.23.0.

Also did some organization, add README.

tools/docker-compose/unit-tests/Dockerfile

@@ -0,0 +1,40 @@
+# FROM gcr.io/ansible-tower-engineering/tower_devel:latest
+FROM centos
+
+RUN yum install -y epel-release
+
+RUN yum install -y \
+	python-pip \
+	python-virtualenv \
+	make \
+	swig \
+	git \
+	libffi-devel \
+	openssl-devel \
+	libxml2-devel \
+	xmlsec1-devel \
+	xmlsec1-openssl-devel \
+	gcc \
+	gcc-c++ \
+	/usr/bin/pg_config \
+	openldap-devel \
+	postgresql-devel \
+	libtool-ltdl-devel
+
+# NOTE: The following steps work for tower-3.0.0
+# RUN curl -LO https://rpm.nodesource.com/pub_0.12/el/7/x86_64/nodejs-0.12.9-1nodesource.el7.centos.x86_64.rpm
+# RUN yum install -y nodejs-0.12.9-1nodesource.el7.centos.x86_64.rpm
+# RUN rm nodejs-0.12.9-1nodesource.el7.centos.x86_64.rpm
+
+# Remove the 2 lines below and uncomment the 3 lines above to build
+# RPMs with the old JS build system.
+RUN curl --silent --location https://rpm.nodesource.com/setup_6.x | bash -
+RUN yum install -y nodejs
+
+RUN npm set progress=false
+
+WORKDIR "/ansible-tower"
+
+ENV VENV_BASE="/venv"
+ENTRYPOINT ["/bin/bash", "-c"]
+CMD ["bash"]

tools/docker-compose/unit-tests/README.md

@@ -0,0 +1,15 @@
+Run from the root of the repo:
+
+```shell
+$ docker-compose -f tools/docker-compose/unit-tests/docker-compose.yml run unit-tests
+```
+
+This will start the container, install the dependencies, and run the unit tests.
+
+If you just want to pop into a shell and poke around, run:
+
+```shell
+$ docker-compose -f tools/docker-compose/unit-tests/docker-compose.yml run unit-tests bash
+```
+
+If you run into any weirdness, it's probably a good idea to just give up and `make clean`.

tools/docker-compose/unit-tests/docker-compose.yml

@@ -0,0 +1,13 @@
+---
+version: '2'
+services:
+  unit-tests:
+    build:
+      context: ../../../
+      dockerfile: tools/docker-compose/unit-tests/Dockerfile
+    environment:
+      SWIG_FEATURES: "-cpperraswarn -includeall -I/usr/include/openssl"
+    command: ["make requirements_test test"]
+
+    volumes:
+      - ../../../:/ansible-tower