Added RFC for "yarn show"

[bhushan-shah-dev]

Added RFC for a new command yarn show, inspired by this issue.

[ljharb]

The spelling “show” conflicts conceptually with npm show; I’d suggest finding an unused name.

[bhushan-shah-dev]

Good point.

How about yarn explicit?

[fivethreeo]

Explicit is a «keyboardful» yarn showdeps or yarn versions or yarn dependencies

[kesor]

If someone is actually using yarn list --depth=0 and parses the output, and after that issue is fixed they would get a different output ... is it really a "breaking" change?

Is it really so essential to introduce yet another subcommand that does exactly what 99% of people intuition is already telling them that yarn list --depth=0 should be doing?

Introducing yet another command is bad UX. Good UX is when you do what the people feel intuitively should "just work".