var contactNum = 0;
   
function add_contact(key, title, cell, email) {
    var tr = document.getElementById(key+'_addPoint');
    var parent = tr.parentNode;

    contactNum++;

    var newNode = tr.cloneNode(true);
 
    var tags = newNode.getElementsByTagName('input');
    for (var i = 0; i < tags.length; i++) {
        var input = tags.item(i);
        input.value = '';
        input.name = input.name + '_'+contactNum;
    }

    parent.appendChild(newNode);
}