Update gesture.js
Update gesture.js

Add skin color detector for more accuracy, you can change the value of range on HSV values to  get more positive values, this values can be related with the lighting
allengaller/reveal.js,Sirlsliang/reveal.js,willy-vvu/reveal.js,ERKKAT001/testing,mrshu/reveal.js-gesture,willy-vvu/reveal.js,stringworld/reveal.js,stringworld/reveal.js,Sirlsliang/reveal.js,allengaller/reveal.js,ERKKAT001/testing