For cref: move compile-directory. Punt sf- and compile-directory?.

For cref: move compile-directory.  Punt sf- and compile-directory?.

Sf-directory? and friend appear to have been broken since
directory-processor started expecting output-type to be a thunk.

Moving compile-directory out of sf/butils.scm and into
compiler/base/toplev.scm eliminates free variable references noted by
CREF.