Imports of structlayout-optimize command

PathSynopsis
encoding/jsonPackage json implements encoding and decoding of JSON as defined in RFC 7159.
flagPackage flag implements command-line flag parsing.
fmtPackage fmt implements formatted I/O with functions analogous to C's printf and scanf.
honnef.co/go/tools/lintcmd/version
honnef.co/go/tools/structlayout
logPackage log implements a simple logging package.
osPackage os provides a platform-independent interface to operating system functionality.
sortPackage sort provides primitives for sorting slices and user-defined collections.
stringsPackage strings implements simple functions to manipulate UTF-8 encoded strings.