If stdin is in use, it'll now be put into non-canonical mode. This is almost
the same as libkrocif's behaviour, except I've set VTIME to 0, since I don't
think there's a good reason to have a terminal read complete if no characters
are available.
This also sets CCSP's branding to "Tock", so error messages now start "Tock: ".
Or, rather, add a new CIF-specific header, so tock_support.h is now the common
code and each of the backends has its own. This means some of the conditional
stuff can go away.