Qualify Ottoman the stool

BUR #30979 has been approved by @nonamethanks.

rename ottoman -> ottoman_(furniture)
deprecate ottoman

The tag "ottoman" is meant to be used for a specific type of stool. But due to how obscure it is, it is frequently mistagged with posts related to the Ottoman Empire. So it's time to change this.

If it's renamed it should first be cleared out of any mistags

岩戸鈴芽 said:

If it's renamed it should first be cleared out of any mistags

I've already checked and Damian seems to be cleared all the mistagged posts from that tag, so it's 100% clear for rename.

The bulk update request #30979 (forum #305346) has been approved by @nonamethanks.