Set install_method and include nodejs::default

Instead of explicitly calling `nodejs::install_from_package` or `nodejs::install_from_source`, set `node['nodejs']['install_method']` and include the default nodejs recipe, which will call the appropriate install recipe.

This lets me specify install_method as an override attribute in my wrapper/app cookbook to use `nodejs::install_from_binary`, which is about 1 million times faster :)