New display mode and uniforms per shader

With the new display mode it is possible to work on a shader and see the results of code changes almost instantaneously. Shader compilation is triggered automatically by any change of the shader code without interrupting the editing process.

Whenever the shader does not compile successfully an error message is shown as usual at the top of the editor and the render view is cleared. Since compilation is invoked automatically during editing error highlighting in the shader code is disabled to not disrupt the editing flow.

Furthermore, clear color, material colors, light position, blending parameters and custom uniforms are now saved for each shader separately. The new feature vastly improves the ability of switching between different shaders without loosing specific uniform configurations. This is especially helpful when utilizing the full flexibility provided by defining up to 20 custom uniforms per shader.

All custom uniforms that were created before this update are copied automatically to your own shaders (excluding the built-in shaders). After the update all changes made to the custom uniforms are saved to the active shader only.