Makes `CelSprite` unowned and adds a new `OwnedCelSprite` class for
owned sprites.
This clarifies ownership and makes the code cleaner in a number of
places.
Additionally, because the `CelSprite` class is now tiny (1 less
pointer), we can pass it by-value instead of by-reference, removing a
pointer indirection in the rendering functions.
1. Increase line height for CJK labels (10->18) to prevent overlap.
2. Increase label width in the right column by 1px (67->68), allowing 3 fullwidth characters to fit on one line.
3. Adjust Base/Now/Gold attribute header positions for CJK.
4. Fix field label/value alignment.
Gleb Mazovetskiy
KPhoenix
qndel
Anders Jenbo
Juliano Leal Goncalves