v0.2.1

GraphNeuralNetworks v0.2.1

Diff since v0.2.0

Closed issues:

• register package (#5)
• Problem with GNNChain and NNConv (#49)

Merged pull requests:

• add nodes/edges softmax and readout (#48) (@CarloLucibello)
• better handling of chain with only graph input (#50) (@CarloLucibello)