Recreate Dockerfile

- Update to Python 3
- Simpler installation, remove docker-stacker script
- Add apk 'make' package. Useful for CI/CD builds

Author: Steven Ringo

Diff for: Dockerfile

@@ -1,13 +1,10 @@
-FROM python:2.7.10
-MAINTAINER Mike Barrett
-
-COPY scripts/docker-stacker /bin/docker-stacker
-RUN mkdir -p /stacks && pip install --upgrade pip setuptools
-WORKDIR /stacks
-COPY . /tmp/stacker
-RUN pip install --upgrade pip
-RUN pip install --upgrade setuptools
-RUN cd /tmp/stacker && python setup.py install && rm -rf /tmp/stacker
-
-ENTRYPOINT ["docker-stacker"]
-CMD ["-h"]
+FROM python:3.7-alpine
+RUN apk add --no-cache make
+WORKDIR /app
+COPY setup.cfg setup.py README.rst CHANGELOG.md ./
+COPY stacker/ ./stacker
+COPY scripts/ ./scripts
+RUN python setup.py install
+WORKDIR /project
+ENTRYPOINT ["stacker"]
+CMD ["--help"]