Release v1.1.280

Changes since v1.1.251:

• Level: better hint in Kaaaart Race.
• Level: make clear where the “lap” starts in Kaaaart Race.
• Level: fix another render glitch near the ending.
• Video capture: higher default frame timeout; fixes timeout at end of capture.
• Engine: improve handling of out-of-screen pixels when scrolling/blurring.
• Engine: slightly speed up some shaders.
• Engine: show game save errors when hitting a checkpoint.
• Engine: add more dither modes.
• Engine: minor module update.