On locales that don't use period as a separator this would break us.
For vector values in a configuration, we use comma as a separator which causes the configuration to balloon to massive sizes due to never saving them
correctly. Loading would then break since it would load a million configuration options.
Fixes issue #7569.
This catches most instances of configuration failures that can happen in a post processing shader.
Gives a user a helpful error message that lets them know what they have failed to set up correctly
This class loads all the common PP shader configuration options and passes those options through to a inherited class that OpenGL or D3D will have.
Makes it so all the common code for PP shaders is in VideoCommon instead of duplicating the code across each backend.
