update random to use ratio
update random to use ratio

dabassett/TinyColor,bgrins/TinyColor,mwcz/TinyColor,mwcz/TinyColor,pandabamboo90/TinyColor,vxvinh1511/TinyColor,bgrins/TinyColor,dabassett/TinyColor,weepy/TinyColor,weepy/TinyColor,vxvinh1511/TinyColor,GerHobbelt/TinyColor,pandabamboo90/TinyColor,GerHobbelt/TinyColor