allow dispatch types to be declared for built-in functions * mk-builtins.pl, gendoc.pl: Handle "classes: NAME ..." info in DEFUN macros. * defun-int.h, defun.cc (install_builtin_dispatch): New function. symtab.h (symbol_tableinstall_built_in_dispatch, symbol_table::fcn_info::install_built_in_dispatch, symbol_table::fcn_info::fcn_info_rep::install_built_in_dispatch): New functions. * svd.cc (Fsvd): Add "classes: double single" tag prior to doc: comment.

--- a/libinterp/corefcn/svd.cc	Wed Dec 14 13:27:08 2016 -0500
+++ b/libinterp/corefcn/svd.cc	Wed Dec 14 14:59:27 2016 -0500
@@ -66,6 +66,7 @@
 }
 
 DEFUN (svd, args, nargout,
+       classes: double single
        doc: /* -*- texinfo -*-
 @deftypefn  {} {@var{s} =} svd (@var{A})
 @deftypefnx {} {[@var{U}, @var{S}, @var{V}] =} svd (@var{A})