Update sln, vcxproj file for Visual Studio 2012 Express
Modify dll/common/Environment.props, remove unused empty elements
Disable ALWAYS_ASSERT preprocessor definition
Add 'Config' class
Modify callback/callback.cpp, save mesh and scene data into .dxrip
directory
Refactor design change, rename repository directory '.dxrip/frame' ->
'.dxrip/scene'
Modify 'dxrip.Init' class, create 'mesh' and 'scene' directory under
'.dxrip'
Merge branch 'save_mesh_into_dxrip_directory' into develop