Added examples and versioning detail to README.

Author: mrbiggred

README.md

@@ -1,2 +1,115 @@
 # Ruby 1.9.3 Docker Image
-A Docker image that contains the latest versions of [RubyGems](https://github.com/rubygems/rubygems), [Bundler](https://bundler.io/), etc that are compatible with Ruby 1.9.3.
+A Docker image that contains the latest versions of [RubyGems](https://github.com/rubygems/rubygems), [Bundler](https://bundler.io/), etc that are compatible with Ruby 1.9.3.  So instead of having to create Dockerfiles that looked like:
+
+```dockerfile
+FROM ruby:1.9.3
+
+# Install stuff
+RUN apt-get update -qq && apt-get install -y build-essential
+
+# Working folder.
+RUN mkdir /app
+WORKDIR /app
+COPY . .
+
+# Install Gems.  Use Bundler 1.17.3 as 2+ does not work with
+# Ruby 1.9.3.  Also update the rubygems to prevent frozen string
+# errors.  Rubygems 2.7.8 is the latest version to support Ruby 1.9.3.
+RUN gem install rubygems-update -v 2.7.8
+RUN update_rubygems
+RUN gem install bundler -v 1.17.3
+RUN bundle install
+```
+
+The files now look like:
+
+```dockerfile
+FROM corigbytes/ruby-1.9.3:1.0.0`
+
+# Working folder.
+RUN mkdir /app
+WORKDIR /app
+COPY . .
+
+# Install Gems.
+RUN bundle install
+```
+
+# Getting the Image
+You can find the image on DockerHub [here](https://hub.docker.com/r/corgibytes/ruby-1.9.3).  To get the latest version, which is not guaranteed to be stable:
+
+`docker pull corgibytes/ruby-1.9.3`
+
+To get a specific version, which is stable:
+
+`docker pull corgibytes/ruby-1.9.3:<version>`
+
+For example:
+
+`docker pull corgibytes/ruby-1.9.3:1.0.0`
+
+Example Dockerfile and Compose to run a Rails app that uses Ruby 1.9.3:
+
+```dockerfile
+# Dockerfile
+FROM corigbytes/ruby-1.9.3:1.0.0`
+
+# Working folder.
+RUN mkdir /app
+WORKDIR /app
+COPY . .
+
+# Install Gems.
+RUN bundle install
+```
+
+```yml
+# docker-compose.yml
+version: '3.7'
+services:
+  web:
+    build: .
+    command: bundle exec rails s -p 3000 -b '0.0.0.0'
+    entrypoint: ./docker-entrypoint.sh
+    volumes:
+      - .:/app
+      - bunlder-data:/user/local/bundle
+    ports:
+      - "3000:3000"
+    depends_on:
+      - db
+      
+  db: 
+    image: postgres:9.6
+    ports:
+      - "5432:5432"
+    environment:
+      POSTGRES_PASSWORD: password1234
+    volumes:
+      - db-data:/var/lib/postgresql/data
+
+volumes:
+  db-data:
+  bundler-data:
+```
+
+```bash
+# docker-entrypoint.sh
+#!/bin/sh
+
+rm -f tmp/pids/server.pid
+exec "$@"
+```
+
+# Versioning
+This image is setup using DockerHub's automate builds.  It will build on every commit to master and tag it as `latest`.  It will build also build on every tag that has the format `v.#.#.#` and tag the build as `#.#.#`.   For example if a release is tagged as `v.1.0.0` a DockerHub image will be created with the tag `1.0.0`.
+
+The tagged versions are stable where as the latest version is not guaranteed to be stable.
+
+You can find a full list of the built tags on [DockerHub](https://hub.docker.com/r/corgibytes/ruby-1.9.3/tags).
+
+# Contributing
+If you have any questions, notice a bug, or have a suggestion/enhancment please let me know by opening [issue](https://github.com/corgibytes/ruby_193_docker/issues) or [pull request](https://github.com/corgibytes/ruby_193_docker/pulls).
+
+# Acknowledgements
+Thanks to the Ruby team for creating orginial [Ruby Docker images](https://hub.docker.com/_/ruby).