Changes needed to be able to build with SWIG 1.3.24, 1.3.27 as well as

Changes needed to be able to build with SWIG 1.3.24, 1.3.27 as well as
the upcoming 1.3.28, using #if statements on SWIG_VERSION.

Adjustments to ownership of SWIG objects, add some destructors and
explicitly disown non-window objects when their ownership is
transfered to a C++ object.

Since all window objects are owned by their parent, or by themselves,
always set their thisown attribute to False.

Explicitly set thisown to False after any Destroy() methods are
called, so SWIG doesn't try to destroy them again.

Etc.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@37205 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775