Badges: honest dates, labels that name one badge, and asking by name

Three things the Elixir Gym found on its first run over the badge tools. First, the date on a badge holder was when the badge last changed, not when Elixir last looked, so a clan read yesterday showed most members as untouched since early September. A holder now carries observed_at, the last profile read, and since, when the record first saw the badge at that level. A since at the start of recording, or just after someone joined, is a first sighting, not when they earned it. Second, the game keeps a few badges in two versions, and both read "Royal Tournament Rank", so the legacy one, held by a single player, looked like the rarest badge in the game. The newer one now says (v2), and the rarity list points out the pair. Third, badges_holders now accepts the name a player uses, like "Valkyrie Mastery", as well as the game's identifier. Contract 6.20.0.