var items = new vis.DataSet([
  {id: 1, content: '1) Next To 2', start: '2014-04-20 00:00:00', end : '2014-04-20 00:59:59'},
  {id: 2, content: '2) Next To 1', start: '2014-04-20 01:00:00', end : '2014-04-20 02:59:59'},
  {id: 3, content: 'Underneath   ', start: '2014-04-20 00:00:00', end : '2014-04-20 05:59:59'}
]);

exports.stack = function...
exports.nostack = function...

var options = {
    margin: {
        item : {
            horizontal : 0
        }
    }
};

var items = new vis.DataSet([
  {id: 1, subgroup:1, content: '1) Next To 2', start: '2014-04-20 00:00:00', end : '2014-04-20 00:59:59'},
  {id: 2, subgroup:1, content: '2) Next To 1', start: '2014-04-20 01:00:00', end : '2014-04-20 02:59:59'},
  {id: 3, subgroup:2, content: 'Underneath   ', start: '2014-04-20 00:00:00', end : '2014-04-20 05:59:59'}
]);

margin: {
        item: 0,
        axis: 0,
        item : {
          horizontal : -25
        }
    },

var options = {
    margin: {
        item : {
            horizontal : -1
        }
    }
};