move parse tree classes inside octave namespace * lex.h, lex.ll, oct-parse.in.yy, parse.h, pt-all.h, pt-arg-list.cc, pt-arg-list.h, pt-array-list.cc, pt-array-list.h, pt-assign.cc, pt-assign.h, pt-binop.cc, pt-binop.h, pt-bp.cc, pt-bp.h, pt-cbinop.cc, pt-cbinop.h, pt.cc, pt-cell.cc, pt-cell.h, pt-check.cc, pt-check.h, pt-classdef.cc, pt-classdef.h, pt-cmd.cc, pt-cmd.h, pt-colon.cc, pt-colon.h, pt-const.cc, pt-const.h, pt-decl.cc, pt-decl.h, pt-eval.cc, pt-eval.h, pt-except.cc, pt-except.h, pt-exp.cc, pt-exp.h, pt-fcn-handle.cc, pt-fcn-handle.h, pt-funcall.cc, pt-funcall.h, pt.h, pt-id.cc, pt-id.h, pt-idx.cc, pt-idx.h, pt-jump.cc, pt-jump.h, pt-loop.cc, pt-loop.h, pt-mat.cc, pt-mat.h, pt-misc.cc, pt-misc.h, pt-pr-code.cc, pt-pr-code.h, pt-select.cc, pt-select.h, pt-stmt.cc, pt-stmt.h, pt-unop.cc, pt-unop.h, pt-walk.h, token.cc, token.h: Move classes and most functions inside octave namespace. Change all uses.

--- a/libinterp/octave-value/ov-fcn.h	Thu Jan 19 14:47:19 2017 -0500
+++ b/libinterp/octave-value/ov-fcn.h	Thu Jan 19 23:41:54 2017 -0500
@@ -35,7 +35,10 @@
 #include "ov-typeinfo.h"
 #include "symtab.h"
 
-class tree_walker;
+namespace octave
+{
+  class tree_walker;
+}
 
 // Functions.
 
@@ -190,7 +193,7 @@
 
   virtual void unload (void) { }
 
-  virtual void accept (tree_walker&) { }
+  virtual void accept (octave::tree_walker&) { }
 
   virtual bool is_postfix_index_handled (char type) const
   { return (type == '(' || type == '{'); }