上拉加载更多，下拉刷新

用法说明

    <scroll :on-refresh="onRefresh" :on-infinite="onInfinite" :no-more='isEnd'>
        <div>内容</div>
    </scroll>

    async onInfinite(done) {
        if(!this.isEnd){
            await this.func();// 异步调用数据
            done()
        }
    },
    async onRefresh(done) {
        await this.func();// 异步调用数据
        done();
    }