Missing roles, only colons

[kovvalsky]

Sometimes a produced AMR can have missing role but a colon:

(vv29traitor / traitor
    :quant (vv29many / many
        :degree (vv29too / too))
    : (vv29compatriot / compatriot
        :poss (vv29we / we)))

P.S. Despite this smatch is fine to translate them into triples that leads to obscure evaluation. smatch issue