tests for binary data

Test that we can write+read and write+recv binary data.
tests for multibyte chars successful

.recv can handle it now, unfudging these tests.
Merge branch 'master' of git://github.com/perl6/roast
expect .recv( bin => True ) to return Buf
Merge branch 'froggs_multibyte' of github.com:perl6/roast
Merge branch 'master' of github.com:perl6/roast