Log Message:
Updated cad/gtkwave to 3.3.79
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3.3.79  31dec16 Disable accelerator keys in twinwave single window mode to
                avoid focus conflicts.
                Fixes for -fstrict-aliasing and other recent warnings.
                Added fill_waveform rc variable and corresponding menu option
                (/View/Show Filled High Values) to allow filling in the lower
                portion of high values for increased visibility.