Imports of package cloudspanner

PathSynopsis
cloud.google.com/go/spannerPackage spanner provides a client for reading and writing to Cloud Spanner databases.
contextPackage context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes.
errorsPackage errors implements functions to manipulate errors.
github.com/google/trillian/merkle/compact
github.com/google/trillian/skylog/storage