Qualify Mario RPG's Booster

BUR #39558 has been approved by @nonamethanks.

rename booster -> booster_(mario_rpg)
deprecate booster

Awfully ambiguous name.

*booster* has 21 entries, sounds reasonable enough. Not so much one of those cases where it might be a one-word tag but for Danbooru purposes people know what they'd be getting if they searched it.

The bulk update request #39558 (forum #345557) has been approved by @nonamethanks.

BUR #39983 has been approved by @nonamethanks.

rename booster_(mario_rpg) -> booster_(super_mario_rpg)

All qualifiers for Super Mario RPG are *_(super_mario_rpg), *_(mario_rpg) breaks convention.

The bulk update request #39983 (forum #347339) has been approved by @nonamethanks.