Added missing pure virtual method wxGraphicsContext::DoDrawText to wxD2DContext
Added ID2D1Factory member to wxD2DRenderer which is created in the ctor and release in the dtor
Fixed issue related to GetHwnd() macro affecting the compilation of d2d1.h
Removed unused wxD2DContext constructors
Implemented wxD2DRenderer::CreateContext(wxWindow*) and implemented a wxD2DContext constructor from a HWND.
Added wxD2DPathData declaration and skeleton implementation