refactored core of gosdn

api/proto/gosdnCLI.pb.go

api/proto/gosdnCLI.proto

api/proto/gosdnCLI_grpc.pb.go

cmd/gosdn-cli/main.go

cmd/gosdn/main.go

configs/clients.toml

configs/gosdn.toml

internal/database/client.go

internal/log/logger.go

internal/log/loglevel.go

internal/nucleus/cli-handling.go

internal/nucleus/controller.go

internal/nucleus/interfaces/client.go

internal/nucleus/interfaces/clientConfig.go

internal/nucleus/nucleus-core.go

internal/restconf/client/ciena/client.go

internal/restconf/util/unmarshal.go