Got it!
var txtFile = new XMLHttpRequest();
txtFile.open("GET", "${resourcesFolderName}/text.txt", true);
txtFile.onreadystatechange = function() {
if (txtFile.readyState === 4) { // Makes sure the document is ready to parse.
if (txtFile.status === 200) { // Makes sure it's found the file.
allText = txtFile.responseText;
//lines = txtFile.responseText.split("\n"); // Will separate each line into an array
var customTextElement = document.getElementById('textHolder');
customTextElement.innerHTML = txtFile.responseText;
}
}
}
txtFile.send(null);