update test: hawk "" prints an empty line

That's what it does in 1.0, at least. I'm not sure that's what we want.
Maybe a syntax error?
remove unused "hawk" function.

the core is now provided by the "processArgs" function.
remove unused QualifiedByteString

It's now a HawkRuntime we pass to hint, so we only need
QualifiedHawkRuntime.