Add Json.by[Key/Index]Value properties for forward compatibility. See #1688.
Add Json.by[Key/Index]Value properties for forward compatibility. See #1688.

gedaiu/vibe.d,DBankov/vibe.d,etcimon/vibe.d,Geod24/vibe.d,rejectedsoftware/vibe.d,chalucha/vibe.d,etcimon/vibe.d