in frontend/src/containers/Home.js [181:193]
handleImgNext() {
const curidx = this.state.selectedImg;
const maxidx = this.state.imglist.length - 1;
var nextidx = curidx + 1;
if(nextidx > maxidx) {
console.log("going back to 0");
nextidx = 0;
}
else {
console.log("incrementing");
}
this.setState({ selectedImg: nextidx});
}