move most functions in variables.cc to octave namespace * variables.h, variables.cc: Move most functions to octave namespace. Provide deprecated inline wrapper functions to preserve old names. Change all uses as needed. (SET_INTERNAL_VARIABLE, SET_NONEMPTY_INTERNAL_STRING_VARIABLE, SET_INTERNAL_VARIABLE_WITH_LIMITS, SET_INTERNAL_VARIABLE_CHOICES): Note that these macros are obsolete. * dirfns.cc, ls-oct-text.cc, pr-flt-fmt.cc, pr-output.cc, svd.cc, ov-base.cc, ov-java.cc, ov-struct.cc, ov-usr-fcn.cc, ov.cc: Eliminate use of SET_INTERNAL_VARIABLE macros.

--- a/libinterp/corefcn/dirfns.cc	Wed Aug 18 09:23:45 2021 -0400
+++ b/libinterp/corefcn/dirfns.cc	Wed Aug 18 11:40:25 2021 -0400
@@ -723,7 +723,8 @@
 @seealso{rmdir}
 @end deftypefn */)
 {
-  return SET_INTERNAL_VARIABLE (confirm_recursive_rmdir);
+  return set_internal_variable (Vconfirm_recursive_rmdir, args, nargout,
+                                "confirm_recursive_rmdir");
 }
 
 OCTAVE_NAMESPACE_END