Fix some dialog and font size concerns.

- Add horizontal layout weights to the picker dialogs in layout-land so that the pickers don't go off screen on smaller devices.
- Copy the original picker layout-land files to layout-w500dp-land where there is enough room for the original layout.
- Update time picker label font sizes from sp to dip for smaller screens so that double-digit hours do not disappear when the Font Size is set to Huge.