Added IRenderable, removed shader programs and allow more nuanced control of render passes, UI items are now rendered same as other scene item components.

src/dawnopengl/display/shader/CMakeLists.txt

@@ -6,7 +6,7 @@
 # Sources
 target_sources(${DAWN_TARGET_NAME}
   PRIVATE
-    ShaderProgram.cpp
+    Shader.cpp
     FontShader.cpp
     SimpleTexturedShader.cpp
     SimpleBillboardedShader.cpp