Added runtime checks  for the conversion functions to verify that all possible enum values are handled
Added a comment documenting the need for the preprocessor defines of the dynamically imported d2d functions
Removed unused section of includes
Reformatted the wxCHECK_* preprocessor definitions and their documenting comments to fit inside the 80 characters line length margin
Shortened the comment documenting the minimum requirements for Direct2D 1.1 by removing unnecessary information.
Pushed the wxUSE_GRAPHICS_DIRECT2D preprocessor guard as early as possible
Renamed m_hasDirect2dSupport to m_hasDirect2DSupport inside the wxDirect2D helper class
Added initial support for dynamically detecting the Direct2D version at runtime
Removed gratuitous empty lines
Reworded the comment documenting wxDirect2D to better fit inside the 80 characters per line limit
Updated wxD2DRenderer::GetVersion to make use of the wxDirect2D version checking support
Broke multiple statements previously on a single line into multiple lines