Toot

* TUI: Fix crash when viewing toot in browser

* Add CONTRIBUTING.md containing a contribution guide
* Add `env` command which prints local env to include in issues
* Add TOOT_POST_VISIBILITY environment to control default post visibility
(thanks Lim Ding Wen)
* Add `tags_followed`, `tags_follow`, and `tags_unfollow` commands (thanks
Daniel Schwarz)
* Add `tags_bookmarks` command (thanks Giuseppe Bilotta)
* TUI: Show an error if attemptint to boost a private status (thanks Lim Ding
Wen)
* TUI: Hide polls, cards and media attachments for sensitive posts (thanks
Daniel Schwarz)
* TUI: Add bookmarking and bookmark timeline (thanks Daniel Schwarz)
* TUI: Show status visibility (thanks Lim Ding Wen)
* TUI: Reply to original account instead of boosting account (thanks Lim Ding
Wen)
* TUI: Refresh screen after exiting browser, required for text browsers (thanks
Daniel Schwarz)
* TUI: Highlight followed tags (thanks Daniel Schwarz)

* Fix packaging issue, missing toot.utils module

* TUI: Press N to translate status, if available on your instance (thanks Daniel
Schwarz)
* Fix: `post --language` option now accepts two-letter country code instead of
3-letter. This was changed by mastodon at some point.
* Fix: Failing to find accounts using qualified usernames (254)

* **BREAKING:** Require Python 3.6+
* Add `post --scheduled-in` option for easier scheduling
* Fix posting toots to Pleroma
* Improved testing

* Remove usage of deprecated `text_url` status field. Fixes posting media
without text.