Fixed a bug with the "Prepend relative source file path to output file" option: This option should not be in effect when "Save output files to the same location where the input file is located" is enabled. Therefore, in the GUI, the "Prepend relative source file path to output file" option was correctly disabled (greyed out) when "Save output files to the same location where the input file is located" was checked. Nonetheless "Prepend relative source file path to output file" could still be in effect, if the user had checked that option *before* it had been disabled (greyed out). This is fixed now.
