Setup CI / CD

[olevitt]

Hello,

At the moment, there is no CI / CD for this project, releases are done manually. We may want to setup a CI system that would :

• Run tests (no tests yet, see #5 )
• Build package
• Publish the package to github releases (maybe maven central one day - see #3 -) on tagged versions

I will submit a PR with a travis-ci configuration as it's the CI used in other InseeFr repos