Add tootctl statuses remove to sweep unreferenced statuses

[Gargron]

Query by @tateisu

Fix #1554

For discussion:

• Name of command
• Interface of command, e.g. options
• Verbosity of command
• The query itself

[nightpool]

needs to handle statuses fetched by threadresolveworker (i.e. root statuses with replies from remote followed accounts).

[tateisu]

even it does not have reply id,it will not deleted.
because it will contains mention to local user.
also toots from remote followed user.

[nightpool]

user A (not followed by anybody) posts
user B replies to A (followed by local user C)

user A's status is fetched by thread resolve worker, but not excluded from this query.

[tateisu]

.where('id NOT IN (SELECT statuses1.in_reply_to_id FROM statuses AS statuses1 WHERE statuses.id = statuses1.in_reply_to_id)') is excludes all statuses that have replies.

[tateisu]

https://gist.github.com/tateisu/c3c13f2580961e86f79889a17f57260a original post about this query

[BenLubar]

A description more precise than Remove statuses might make more admins run it. I only learned what this actually does because I was curious, and I wouldn't have ever run it if I didn't see the query.

[jelutz77]

Just ran this command, and it removed 10GB of about 70GB of data. I have 2 active users on my instance and it's only been running about a month. I spend entire days without interacting, and so does the other user. It seems to me that the command should free up MUCH more space than this?