Consider suggesting or enforcing the use of a node version manager

[javiertoledo]

Managing dependencies is always tricky, and there are some pieces of Booster (especially integration tests) that might be affected by changes made by the user in their global registry. It could be a good idea to consider using nvm or similar tools that allows us to sandbox the npm environment. In this way, we can be sure that all the contributors use the same node version and a more repeatable environment.