RFE: Remove "Shader text" property feature

[skeletonbow]

The "Shader text" property that first appears when you add the "User-defined-shader" property filter to a source has never really worked properly and is just clutter in the user interface that likely confuses some non-developer end users. I doubt there are many developers that would use it either as it is of extremely limited use at best.

Removing this feature would simplify the user interface and reduce non-developer end-user confusion. Nobody would likely miss it, and OBS Shaderfilter 1.21.1 would still exist if they needed to use this for some odd reason.

For this reason, I plan to remove it from my build in the future unless I come across a good enough reason to keep it. The "Load shader text from file" checkbox can then be removed also, and replaced by a "Shader file:" textbox.

Another option to consider, would be to scan the supplied shader examples directory and preload a combo box with all of the shaders so users can just pick one without having to navigate their hard disk, and then have an optional "manually specify shader file" option or something to navigate to a custom location to load a shader file.

All things worth exploring somewhat before committing to any specific changes though.