fix: you should check hasMore before loadMore

[success-cg]

you should check hasMore before loadMore function be called，because in my project，I find a bug: there is not any more data from server, and props.hasMore is false, but your InfiniteScroller will be loadMore once more again. By the way, it's a h5-mobile web. I was debugger , find the offset will be less than 0, such as -78 by calculate, so even if the hasMore is false, but the loadMore function will be called once more; I think, you should check hasMore before loadMore function be called;

[joshuaobrien]

You probably didn't intend to, but you've made unnecessary changes to yarn.lock, as well as deleted dist.