use auto keyword to declare iterator variables where possible * dialog.cc, files-dock-widget.cc, history-dock-widget.cc, file-editor.cc, octave-qt-link.cc, call-stack.cc, debug.cc, dynamic-ld.cc, fcn-info.cc, fcn-info.h, genprops.awk, graphics.cc, gtk-manager.cc, gtk-manager.h, hook-fcn.h, load-path.cc, load-save.cc, ls-mat5.cc, mex.cc, oct-map.cc, oct-stream.cc, octave-link.cc, regexp.cc, symscope.h, symtab.h, txt-eng.h, url-handle-manager.cc, variables.cc, ov-base.cc, ov-class.cc, ov-classdef.cc, ov-fcn-handle.cc, ov-java.cc, ov-struct.cc, bp-table.cc, jit-ir.cc, jit-typeinfo.cc, pt-arg-list.cc, pt-arg-list.h, pt-array-list.cc, pt-check.cc, pt-classdef.cc, pt-decl.h, pt-eval.cc, pt-idx.cc, pt-jit.cc, pt-misc.cc, pt-pr-code.cc, pt-select.h, pt-stmt.h, caseless-str.h, lo-regexp.cc: Use auto keyword to declare iterator variables where possible. Style fixes.

--- a/libinterp/corefcn/octave-link.cc	Wed May 02 00:30:00 2018 -0400
+++ b/libinterp/corefcn/octave-link.cc	Wed May 02 01:36:20 2018 -0400
@@ -257,7 +257,7 @@
       nel -= 2;
       Cell items (dim_vector (1, nel));
 
-      std::list<std::string>::iterator it = items_lst.begin ();
+      auto it = items_lst.begin ();
 
       for (int idx = 0; idx < nel; idx++, it++)
         items.xelem (idx) = *it;