This header declares functions in libobject. Our programs never
included object.h, but called functions in libobject without declaring
them. So, our build system never put object.h in the include path;
any #include <object.h> would fail to find the header.
With this commit, a program may #include <object.h> if it has
modules/src/object+lib in its deps.
Declare structs in object.h so we can use them in prototypes without
gcc warning, "'struct whatever' declared inside parameter list".
Remove inclusion of ansi.h from object.h. Programs would need to
depend on modules+headers to get ansi.h in the include path.