graphics/fotoxx: the port had been updated to version 23.32

• Mute the -Wwritable-strings' warnings (ISO C++11 does not allow conversion from string literal to char *') for the time being: there are tons of them and they clobber the build log, making it hard to look for more important warnings and errors
• While here, make `pkg-plist' better sorted against LC_COLLATE=C