Add CIs config files

[pfernique]

No description provided.

[pradal]

There is perhaps a need to first port the code to Python 3.

[artzet-s]

Why not save one file and use directly the hidden file .travis.yml ?
Why not use hidden file "convention" for ci file with .appveyor.yml (that also works) ? (see on https://github.com/openalea/eartrack)

It's detail but it's more logic for me.

[pfernique]

Because on Linux, the file will be hidden, it's not very convenient for developers that need to modify them