Fixed #11; Make the document root a volume so that it can be mounted

Dockerfile

@@ -26,6 +26,9 @@ RUN chown -R nobody.nobody /run && \
 # Setup document root
 RUN mkdir -p /var/www/html
 
+# Make the document root a volume
+VOLUME /var/www/html
+
 # Switch to use a non-root user from here on
 USER nobody
 

README.md

@@ -36,3 +36,7 @@ Start the Docker container:
     docker run -p 80:8080 trafex/alpine-nginx-php7
 
 See the PHP info on http://localhost, or the static html page on http://localhost/test.html
+
+Or mount your own code to be served by PHP-FPM & Nginx
+
+    docker run -p 80:8080 -v ~/my-codebase:/var/www/html trafex/alpine-nginx-php7