javascript debounce function
// This is from David Walshes Blog Post
// https://davidwalsh.name/javascript-debounce-function
// A very simplified but effective version of Underscores debounce function
function debounce(func, wait, immediate) {
var timeout;
return function() {
var context = this, args = arguments;
var later = function() {
timeout = null;
if (!immediate) func.apply(context, args);
};
var callNow = immediate && !timeout;
clearTimeout(timeout);
timeout = setTimeout(later, wait);
if (callNow) func.apply(context, args);
};
};