yarn build create assets for deployment
yarn start start up dev server
yarn test run tests
currentImg: ({ src: string, caption: string }),
images: [({ src: string, caption: string })],
onPrev: () => void - function that should be invoked when going to the previous image,
onNext: () => void - function that should be invoked when going to the next image,
preload?: bool - optional prop. if true, all images passed in the images array will be preloaded.