Archive Method: Fix Medium RSS feed parsing

[pirate]

➜ ~/D/C/bookmark-archiver py[archiver] ⎇ (ssl-check) ./archive.py "https://medium.com/feed/@thesquashsh"
[*] [2018-01-12 12:23:50] Downloading https://medium.com/feed/@thesquashsh > downloads/medium.com.txt
[X] No links found :(
[1]

[aseeralmeem]

➜ ~/D/C/bookmark-archiver py[archiver] ⎇ (ssl-check) ./archive.py "https://medium.com/feed/@thesquashsh"
[*] [2018-01-12 12:23:50] Downloading https://medium.com/feed/@thesquashsh > downloads/medium.com.txt
[X] No links found :(
[1]

[pirate]

I've confirmed this is working on master:

(venv) ➜ ~/D/C/bookmark-archiver py[venv] ⎇ (cleanup) ./archive "https://medium.com/feed/@thesquashsh"                                                Sun Jun 10 22:02:37 2018
[*] [2018-06-10 22:05:04] Downloading https://medium.com/feed/@thesquashsh > output/sources/medium.com-1528682704.txt
[+] [2018-06-10 22:05:05] Adding 10 new links from output/sources/medium.com-1528682704.txt to output/index.json
[√] [2018-06-10 22:05:05] Updated main index files:
    > output/index.json
    > output/index.html
[▶] [2018-06-10 22:05:05] Updating files for 40 links in archive...

[uriel1998]

Related, so I'm adding this here: RSS feeds from Wallabag and Shaarli both produce "no links found". Fresh install with a pull today. Not sure what's causing the problem, as it imported my shaarli export just fine.

bag.faithcollapsing.com-1543613192.txt
shaarli.stevesaus.space-1543613205.txt