master branch out of date

[colin-nolan]

It is a little confusing when one comes to this repo - expecting to find exciting Docker things - to just see an outdated and uninteresting master branch.

May I suggest that the master branch is kept up to date (how are you guys developing this given there are only release branches and an out of date master?!) or you remove the master and set the default branch to the latest release?

This would provide a little more help to people who want to access and engage with your work.