Ensuring that quality dub packages don't get permanently abandoned

[LorenDB]

I've recently noticed that a lot of the packages available on Dub 
are rather old: 80% of the 1475 packages available haven't been 
updated for at least a year, and around 50% are five years old or 
even older. This is a shame, as there are some really neat 
libraries on Dub that I'd love to use, but I'm just a little bit 
afraid to start using a package that likely won't have any active 
upstream support; even if I were to fix any bugs I found myself, 
there's no good way to get the fix out to others if the original 
author/maintainer isn't around to merge your fixes into the 
upstream repo.

I recently learned about the [Code 
Shelter](https://www.codeshelter.co) project. It looks like a 
really neat resource, and the fellow who started the project says 
that although the Code Shelter seems inactive, it's more due to a 
lack of proper marketing than to people bailing on it. I think 
that the D community could potentially make use of the Code 
Shelter by adopting it for various packages and promoting its 
use. For example, when somebody is adding a new package to 
code.dlang.org, they could be shown a prompt encouraging them to 
add their project to the Code Shelter if they are comfortable 
with that; if a package owner is inactive for a certain amount of 
time, they could be sent an email encouraging them to look into 
the Code Shelter.

I will add the disclaimer that this is just an off-the-cuff idea 
that I want to put out there; however, I think that having a 
package maintenance solution like the Code Shelter in place for 
the Dub package registry would be a big boon to the D ecosystem. 
I'm interested in hearing feedback on this idea :)