travis: bump version to 0.3.1
travis: bump version to 0.3.1

NewEconomyMovement/NemCommunityClient,NewEconomyMovement/NemCommunityClient,NewEconomyMovement/NemCommunityClient,NewEconomyMovement/NemCommunityClient,NewEconomyMovement/NemCommunityClient,NewEconomyMovement/NemCommunityClient