Avoid using KWSys auto_ptr by adopting it ourselves

Replace use of cmsys::auto_ptr with a CM_AUTO_PTR macro that maps to
our own implementation adopted from the KWSys auto_ptr implementation.
Later we may be able to map CM_AUTO_PTR to std::auto_ptr on compilers
that do not warn about it.

Automate the client site conversions:

    git grep -l auto_ptr -- Source/ | grep -v Source/kwsys/ | xargs sed -i \
      's|cmsys::auto_ptr|CM_AUTO_PTR|;s|cmsys/auto_ptr.hxx|cm_auto_ptr.hxx|'

Source/cmLocalVisualStudioGenerator.cxx

@@ -74,12 +74,12 @@ void cmLocalVisualStudioGenerator::ComputeObjectFilenames(
   }
 }
 
-cmsys::auto_ptr<cmCustomCommand>
+CM_AUTO_PTR<cmCustomCommand>
 cmLocalVisualStudioGenerator::MaybeCreateImplibDir(cmGeneratorTarget* target,
                                                    const std::string& config,
                                                    bool isFortran)
 {
-  cmsys::auto_ptr<cmCustomCommand> pcc;
+  CM_AUTO_PTR<cmCustomCommand> pcc;
 
   // If an executable exports symbols then VS wants to create an
   // import library but forgets to create the output directory.