Add option for cursor position

[ghost]

It would be useful to be able to decide if the current position of the video should be in the center or in the beginning- I'm trying to create a video editor and I don't need the trailing first half of the screen before the video begins.

[ingageco]

+1 on this. There's a lot of wasted space early on the waveform, unless i missed the option

[huanghaiyang]

+1