Better implementation for hiding links on negative rshares posts

https://hive.blog/curation/@newsflash/curation-from-this-account

It's been decided to not hide negative rshares posts/comments. However, to protect users from spams/phishing, check URL against whitelist and show an external link confirmation.

mentioned in merge request !331 (merged)

mentioned in commit 1a07d3db

closed with merge request !331 (merged)