Create advice document on how to incorporate brand-new contributors into your project

[jberkus]

One type of potential contributor that now shows up in large numbers in the CNCF community is the brand-new contributor -- someone, often a CS student, who has never contributed to public open source projects before. While these contributors require a lot of mentoring, there are a lot of them, and projects who can welcome them will have a healtier contributor pipeline.

We should write an advice guide on various ways to give brand-new contributors useful ways to contribute without overburdening maintainers.