Wav / 17 - minimize differences to book code

overlooked some
Wav / 17 - micado step 6; reverted all.
Wav / 18 - micado step 1 "using namespace std".
Wav / 19 - Snippet::dataLength().
Wav / 20 - Snippet::Snippet().
Wav / 21 - snippet.h
make rLog() inline

as it needs to be included more than once.
Wav / 22