Imports of package util

PathSynopsis
contextPackage context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes.
encoding/binaryPackage binary implements simple translation between numbers and byte sequences and encoding and decoding of varints.
github.com/tonistiigi/fsutil
ioPackage io provides basic interfaces to I/O primitives.
syncPackage sync provides basic synchronization primitives such as mutual exclusion locks.