v2.2.a

• Implemented PSO compatibility: if two pipeline states share the same shader resource layout, they can use SRB objects interchangeably
• Fixed the following issues:
  • Messy #include structure?
  • Move GetEngineFactoryXXXType and LoadGraphicsEngineXXX to Diligent namespace
  • Customizable build scripts
  • Win32FileSystem releated functions should use wchar_t (UTF-16)