Time Scale Updates for Tooltips

[etimberg]

New Time Scale Option

This addresses #1466

{
    time: {
        // Moment JS Format string used when time scale values go into the tooltip
        tooltipFormat: '', 
    }
}

Issues Fixed

• Fixed time scale sample files. Fixed issue when bars were drawn on a time scale.
• Added a test to cover the time scale when handling date objects
• Used suggested solution from Possibility to use series with Date #1739 to allow time points with date objects. Thanks @zup1