News series listing could be added

[minusQuantumNeko]

Currently it's quite hard to find newsposts from specific series, and there is a list only for osu!monthly right now, so it would be nice to have something like this.

[Walavouchey]

thinking of a structure like this

# News series

blah blah

## Listing

### Series one

explainer paragraph or two

| Title | Publication date |
| :-- | :-- |

## Series two

explainer paragraph or two

| Title | Publication date |
| :-- | :-- |

and a new yaml tag in applicable news posts like so

---
layout: post
title: Series one episode one
series: Series one
date: 2017-08-17 03:00:00 +0000
---

which would allow for easy automation

[cl8n]

something to let me go to previous and next post in a series would be nice. adding yaml tag sounds good

[minusQuantumNeko]

I'm unsure about all series newsposts being listed inside one article, but automation and tags part sounds good

[cl8n]

something to let me go to previous and next post in a series would be nice. adding yaml tag sounds good

I forgot to write an update here, I did look into this but it turned out to be more involved than would be wise for me to work on rn. I added it to a list but u can bug me if this is still not done in some months