Merge "Implement solo orderer" into feature/convergence

orderer/atomicbroadcast/block.go

orderer/main.go

orderer/sample_clients/broadcast_timestamp/client.go

orderer/sample_clients/deliver_stdout/client.go

orderer/solo/broadcast.go

orderer/solo/broadcast_test.go

orderer/solo/deliver.go

orderer/solo/deliver_test.go

orderer/solo/ramledger.go

orderer/solo/ramledger_test.go

orderer/solo/solo.go