Rename production.Dockerfile to development.Dockerfile.

It was a late night, ok? Updated README.md to include removal of DB from repo.

development.Dockerfile

@@ -0,0 +1,14 @@
+FROM python:3.9-slim
+
+WORKDIR /app
+
+# Copy and install Python dependencies.
+COPY requirements.txt requirements.txt
+RUN pip install --no-cache-dir -r requirements.txt
+
+# Copy the rest of the app code.
+COPY . .
+
+EXPOSE 5000
+
+CMD ["python", "app.py"]