Bug Fixes and initial libretro core

[jtothebell]

All Platforms
-Fix behavior when drawing coordinates beyond sprite sheet bounds
-Fix mget bounds check being off by one on upper bounds (fixes some visual artifacts in map() and tline() calls)
-Fix some text wrapping bugs
-Fix some text coloring bugs
-Fix bugs keeping track of smaller than default character size and line heights
-Fix a bug with music playback where looping sections were cut short (thanks @fringd)

Miyoo Mini (standalone app)
-Add double buffering to fix occasional screen tearing

New Platforms
-Add experimental libretro builds for Miyoo Mini and Android

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This discussion was created from the release Bug Fixes and initial libretro core.

[deliyuerek85]

Thank you very much for the retroarch/libretro core. It works like a charm on my android system.

[54MU3L3990]

OPK isn't working on rg350. If you try to boot a pico game, It goes black for a split second and sends you back to the menu.