Initial port of wxPython demo from Classic to Phoenix.

Pulled and squashed from https://github.com/RobinD42/Phoenix/pull/7
Thanks Metallicow!

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxPython/Phoenix/trunk@74199 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775