Add topic Hacktoberfest to repo

[afucher]

Hey @Kibo,

Don't know if you heard about Hacktoberfest, it's a great opportunity to have nice contributions to your code.

To make this repo a valid one, you need to opt-in adding the topic hacktoberfest to this repo. As a participant of Hacktoberfest and a contributor, I'll be very glad if you could do this.