Feature request: Add greylist for individual posts using search

[ghost]

Basically a few posts come up very frequently on the search because of the sheer number of tags they have, the 1000 character derpi collabs and 2231725 are the main ones I've seen. It would be nice to have a greylist where the posts won't show up under normal search but will still show if you use the >> and id:1234 syntax.

Some other ideas in no particular order (and some conflict with the above)

• Override when you add wall of tags to the search?
• Instead automatically greylist things with an arbitrary tag like great wall of tags?
• Instead greylist anything with more than x amount of tags (some stupid high limit like 1000). I have no idea if this is even feasible to code without it being ugly.