[Nix-dev] PR [member] label

[Michael Raskin]

I propose to add a [member] label to PR labels. This label is to be
applied to pull requests that are created by the project committers.

Rationale: it is a good idea to look at long-standing non-member PRs.
And ideally "long-standing" means "half a week".

1. I think we all admit that we have a problem with timely merging of 
pull requests.

2. I hope we all agree that we want to attract new committers.

A first-time contributor feeling ignored often has no idea what are the
chances to get the PR merged or even to get any feedback. There are
times when negative feedback is the best reaction; but lack of feedback
to the first-time PR submitter is never something we _want_, it just
happens. 

If a long-time member creates a PR, it is a clear signal that quick
merge is not seeked; there is a discussion to be had, and if there are 
no opinons, merging own PRs is always an option.

If a fresh committer creates a PR, quick merge may be or may not be
a desired outcome; but anyway there is some confidence and some
understanding about whom to ping and some other small fixes can be
pushed in the meantime.

To solve this problem some of the project members try to look at PRs and
merge as much as possible. To make this as straightforward as possible
we should have a label to filter out PRs not intended for speedy
reaction. I think [member] label is a good approximation. It can be 
applied without thinking, it is convenient to filter by -label:member, 

I hoped there is a way to just write something like 
-author:in-team:nixpkgs-committers, but apparently Github doesn't have
this and we need to emulate this manually.