disambiguate phone_screen + cellphone_picture

BUR #17623 has been approved by @nonamethanks.

create alias phone_screen -> fake_phone_screenshot
create implication fake_phone_screenshot -> fake_screenshot

this tag is for fake screenshots of cellphone screens, yet people frequently confuse it with cellphone picture, the tag for phone screens in images, because they don't read wikis. I think this is the clearest it can possibly be in the name, but more suggestions are welcome. I'll go through and fix the mistags as applicable later.

BUR #17624 has been rejected.

remove alias phone_screen -> fake_phone_screenshot
create alias cellphone_picture -> phone_screen

part 2, approve/reject the first before this one

I find "phone screen" to be a more intuitive name for describing visible phone screens in images than cellphone picture (and if the volume of mistags are any indication, a lot of people agree) so changing the tag name might not be a bad idea.

there will be an unalias phone_screen -> fake_phone_screenshot line added to the BUR if the first passes to accommodate for renaming cellphone picture; unaliasing might temporarily throw off people already using phone screen as intended, but I think this will help the majority of users.

The bulk update request #17623 (forum #244804) has been approved by @nonamethanks.

These tags need some serious cleanup.

This bulk update request is pending automatic rejection in 5 days.

I'm not really convinced that phone screen won't just be mistaken for fake phone screenshot.

This bulk update request has been rejected because it was not approved within 45 days.

The bulk update request #17624 (forum #244808) has been rejected by @DanbooruBot.

BUR #18785 has been approved by @nonamethanks.

remove alias phone_screen -> fake_phone_screenshot

Removing this alias for now.

The bulk update request #18785 (forum #249397) has been approved by @nonamethanks.