Add back in revive summoner spell

Open spell book rune is a really cool concept, but really has no meaniful application. Most people just trade out one of their summoner spells one time (early game ignite to late game cleanse or exhaust). If revive was added back in as a summoner spell it could prove very useful in games depending on the situation.

Enemy team trying to baron and your dead? Change out to revive.

Is it past 45 mins and you got caught out and there's no way your team can 4v5? Change out revive.

I believe this will make open spell book a much more attractive option.