Imports of getgo command

PathSynopsis
archive/tarPackage tar implements access to tar archives.
archive/zipPackage zip provides support for reading and writing ZIP archives.
bufioPackage bufio implements buffered I/O. It wraps an io.Reader or io.Writer object, creating another object (Reader or Writer) that also implements the interface but provides buffering and some help for textual I/O.
bytesPackage bytes implements functions for the manipulation of byte slices.
compress/gzipPackage gzip implements reading and writing of gzip format compressed files, as specified in RFC 1952.
contextPackage context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes.
crypto/sha256Package sha256 implements the SHA224 and SHA256 hash algorithms as defined in FIPS 180-4.
encoding/jsonPackage json implements encoding and decoding of JSON as defined in RFC 7159.
errorsPackage errors implements functions to manipulate errors.
flagPackage flag implements command-line flag parsing.
fmtPackage fmt implements formatted I/O with functions analogous to C's printf and scanf.
golang.org/x/sys/execabsPackage execabs is a drop-in replacement for os/exec that requires PATH lookups to find absolute paths.
ioPackage io provides basic interfaces to I/O primitives.
io/ioutilPackage ioutil implements some I/O utility functions.
net/httpPackage http provides HTTP client and server implementations.
osPackage os provides a platform-independent interface to operating system functionality.
os/userPackage user allows user account lookups by name or id.
path/filepathPackage filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths.
runtimePackage runtime contains operations that interact with Go's runtime system, such as functions to control goroutines.
stringsPackage strings implements simple functions to manipulate UTF-8 encoded strings.