Clip and Timecode Display

Several improvements have been made to clip and timecode display in Batch.

You can now change the timecode of a clip brought into Batch so that it corresponds to Batch time.
You can display or hide negative frames that result from offsetting the starting frame of a clip in main Batch.
When you load a clip into Batch, you can now display head and tail frames in the Batch timebar. Previously you could only display head frames.