Update links

Updates some links to their new locations, and
replaces some http:// with https:// links.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

docs/rails.md

@@ -30,7 +30,7 @@ Dockerfile consists of:
     RUN bundle install
     ADD . /myapp
 
-That'll put your application code inside an image that will build a container with Ruby, Bundler and all your dependencies inside it. For more information on how to write Dockerfiles, see the [Docker user guide](https://docs.docker.com/userguide/dockerimages/#building-an-image-from-a-dockerfile) and the [Dockerfile reference](http://docs.docker.com/reference/builder/).
+That'll put your application code inside an image that will build a container with Ruby, Bundler and all your dependencies inside it. For more information on how to write Dockerfiles, see the [Docker user guide](https://docs.docker.com/engine/userguide/dockerimages/#building-an-image-from-a-dockerfile) and the [Dockerfile reference](https://docs.docker.com/engine/reference/builder/).
 
 Next, create a bootstrap `Gemfile` which just loads Rails. It'll be overwritten in a moment by `rails new`.
 
@@ -128,7 +128,7 @@ Finally, you need to create the database. In another terminal, run:
 
     $ docker-compose run web rake db:create
 
-That's it. Your app should now be running on port 3000 on your Docker daemon. If you're using [Docker Machine](https://docs.docker.com/machine), then `docker-machine ip MACHINE_VM` returns the Docker host IP address.
+That's it. Your app should now be running on port 3000 on your Docker daemon. If you're using [Docker Machine](https://docs.docker.com/machine/), then `docker-machine ip MACHINE_VM` returns the Docker host IP address.
 
 
 ## More Compose documentation