#24 Manual.txt needs dynamic-wind

[Doug Currie]

The Manual.txt says

There are no hygienic macros. No rational or
complex numbers. No unwind-protect and call-with-values.

but the CHANGES file says

Added unwind-protect (tehom)

Nevertheless, there is no unwind-protect (though there is a dynamic-wind).

Manual.txt also has

There is no call-with-values, values, nor dynamic-wind. Dynamic-wind in
the presence of continuations would require support from the abstract
machine itself.