Fix the handling of string variable - store them as UTF-8 into the config variables...

Fix the handling of string variable - store them as UTF-8 into the config variables, also convert the StringList values to an UTF8 string before putting them into a QVariant - which seems not to work if created from a "char *" - because later converterd QVariant->toString() isn't UTF8 like expected.
waveout.c forgott to convert string to UTF8 before storing in choice list