feature: Relative GF to Saturation renames Rename relevant code from Relative GF to Saturation. Involving UI elements, variable names, translated texts (that still need to be done), etc. No functional changes. Notice that I chose super_saturation as name, to provide a better link to the hwOS repo. Further notice that the TXT variable name is not changed. This is intensional, as there is also a desaturation variable, so things might get confusing renaming the TXT variable name. Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>