Leading 0's in SementTemplate and IE11 meta tag

Hello,

I'm submitting a patch which adds the following to the Dash.js player:

- Added the capability to handle SegmentTemplates which use leading 0's in the $Number%04d$ format. (Hex and Decimal formats)
- Added a meta tag to prevent IE 11 from using compatibility mode when running the player.
- Fix for the handling of SegmentTimeline@t when r>0.

I hope you find this useful.

Tim Williams
Digital TV Labs.