Update Meteor 1.6, Node 6.12 and NPM versions to Dockerfile.
Update Meteor 1.6, Node 6.12 and NPM versions to Dockerfile.

wekan/wekan,johnleeming/wekan,nztqa/wekan,nztqa/wekan,nztqa/wekan,johnleeming/wekan,wekan/wekan,GhassenRjab/wekan,wekan/wekan,wekan/wekan,johnleeming/wekan,johnleeming/wekan,GhassenRjab/wekan,libreboard/libreboard,wekan/wekan,libreboard/libreboard,GhassenRjab/wekan