Add missing commas to test vectors

ok tb@

Add test coverage for SHA3

ok tb@

Add two const

Make test tables static const and fix a style nit

Add tests for 1 million repeated "a"

From Joshua Sing

Add a nicely licensed, table-driven test for SHA

This tests covers the NIST vectors for SHA-{1,224,256,384,256} and will
soon be able to replace the old SHA tests entirely.

From Joshua Sing <joshua () hypera ! dev>