You can read a file via JavaScript from the page.  You cannot upload a file to the developer's console.
I then modified the code bellow a bit to help you further.  I added a scrape function that will help you request each  URL one at a time.
  <div id="page-wrapper">
        <h1>Text File Reader</h1>
        <div>
            Select a text file: 
            <input type="file" id="fileInput">
        </div>
        <pre id="fileDisplayArea"><pre>
    </div>
<script>
function scrape(urls) {
    url = urls.shift()
    $.get(function (url) {
        // get the url data here
        scrape(urls);
    });
}
window.onload = function() {
        var fileInput = document.getElementById('fileInput');
        var fileDisplayArea = document.getElementById('fileDisplayArea');
        fileInput.addEventListener('change', function(e) {
            var file = fileInput.files[0];
            var textType = /text.*/;
            if (file.type.match(textType)) {
                var reader = new FileReader();
                reader.onload = function(e) {
                    scrape(reader.result.split("\n"));
                }
                reader.readAsText(file);    
            } else {
                fileDisplayArea.innerText = "File not supported!"
            }
        });
}
</script>
Modified version of:
Read a local text file using Javascript