Add dockerization

[vsambor]

Docker images for our project

• Image for NodeJs

• Image for Mongodb which is linked to Node image

• Image for VueJS

[iliasnaamane]

• In our project we will have to build three docker files, so I suggest to have a folder which contains the three docker files.

• I propose to use this pattern for CI using Docker and Travis: https://medium.com/mobileforgood/patterns-for-continuous-integration-with-docker-on-travis-ci-71857fff14c5