Kivy labeling

[bw4sz]

1. Label minsize (0-100) so people know that 0.1 is 0.1% of a frame.
2. Make font size of minsize bigger
3. Text label for slide to show that moving to the right will return fewer frames.
4. I think the font in general can be bigger.
5. File selector.
6. Go to folder after output option.