Apache Sling Launchpad - Docker integration

The Launchpad Docker integration project is a helper aimed to make it
simple to build an 'official' Sling docker image.

Building a Docker image
---------------------------------------------

$ docker build -t sling .

Running a standalone Sling instance
---------------------------------------------

To launch a docker instance named 'my-sling-container' bound to 
port 8080 on the local machine, and with the /opt/sling/sling volume
mounted at /srv/docker/sling in the local machine, execute:

$ docker run -ti -p 8080:8080 -v /srv/docker/sling:/opt/sling/sling \
    --name my-sling-container sling


Running a Sling instance connected to MongoDB
---------------------------------------------

There is a docker-compose-mongodb.yml file supplied which shows how to run
the Sling launchpad in a docker container linked to a mongo one. To launch
both containers, execute:

$ sudo docker-compose -f docker-compose-mongo.yml up

Pushing the docker image to DockerHub
----------------------------------------------

This assumes that you have the credentials for the apachesling repository
on DockerHub.

First of all, build the image tagged for the apachesling repository. You
should tag it with both the 'latest' and the version number of the launchpad
release. For the 8 release, this would translate into

$ docker build -t apachesling/sling:8 .
$ docker build -t apachesling/sling:latest .

Then, push the image

$ docker push apachesling/sling:8
$ docker push apachesling/sling:latest