Add new md

I add this .md just to list some steps I think could help us to keep a good workflow for everyone. If you do not agree, please, make suggestions and etc. here on the pull request.

And feel free to say if you think everything here is expendable. 

Also, feel free to change and improve the way it was written as I don't have a good english knowledge (@oliviagj)

The WORKFLOW.md file can be seen here: https://github.com/RocketBoard/rocketboard/blob/ramon-add-new-md/WORKFLOW.md