Feature request: Hide boost of toots of accounts I follow

[Inrumpo]

This feature request originated from a short discussion in #384.

Goal

Do not show toots I've already seen (via boosts).

Use Cases

• A user I follow has posted a toot. I see that toot. One day later he is boosting his own toot. This will show me that toot again.
• I follow user A and B. User A has posted a toot. I see that toot. One day later user B is boosting that toot from user A. This leads to that toot appearing in my timeline for the second time.

Requested solution (feature)

Give the user an option to hide boosted toots that were originally posted by people they follow.