Doesn't serialize (repeated fields)

[Jacek Sieka]

type Xxx {.protobuf3.} = object
  xxx {.fieldNumber: 1.}: seq[uint32]

echo Protobuf.encode(Xxx(xxx: @[2'u32, 3, 4]))

the above message silently compiles and outputs an empty seq

[Jacek Sieka]

#36