added docker support

reworked backend to allow for containerization. config items can now be overwritten by environment vars

fixed bug during building

updated youtube-dl version in backend

Dockerfile

@@ -0,0 +1,28 @@
+FROM ubuntu:18.04
+
+RUN apt-get update && apt-get install -y \
+  nodejs \
+  apache2 \
+  npm \
+  youtube-dl
+
+# Change directory so that our commands run inside this new directory
+WORKDIR /var/www/html
+
+# Copy dependency definitions
+COPY ./ /var/www/html/
+
+# Change directory to backend
+WORKDIR /var/www/html/backend
+
+# Install dependencies on backend
+RUN npm install
+
+# Change back to original directory
+WORKDIR /var/www/html
+
+# Expose the port the app runs in
+EXPOSE 80
+
+# Run the specified command within the container.
+CMD ./docker_wrapper.sh