div0 and fix

[ivannunyadambiz]

the library actually works with the esp32, but needs a little fix

bassdll.cpp, line 90: was: halflife = 500000/fixTone(notes[current]->tone + transpose); fixed:

int tempdiv = fixTone(notes[current]->tone + transpose);
if(tempdiv != 0) halflife = 500000/tempdiv;
else halflife = INT_MAX;