time); delete some comments that didn't add much and were incorrect
anyway (the test specification was tc, not t).
R=jcb
CC=agl, golang-dev
https://golang.org/cl/7665045
Added a pure Go implementation of SHA3 (Keccak) which implements the hash.Hash interface.
A test file is included with performance benchmarks and standard test vectors.
R=agl, nigeltao
CC=golang-dev
https://golang.org/cl/7760044