This patch does a few things:
* Prevents the loss of invincibility frames when auto reserves activate (no more getting hit twice!)
* Prevents heat damage when auto reserves activate
* Prevents a crash when pausing while auto reserves are active.
* Fills Samus' reserve health when you pick up a reserve tank so that you don't have to fill it yourself first.

If you think of other ways reserves can be fixed, let me know! This patch has been updated a few times to tweak some things to continue to make reserves less sucky.

I also have another resource which indicates when reserves are full on your HUD: https://metroidconstruction.com/resource.php?id=546

No freespace is used.
Credit to Lioran for inspiration, PJBoy for bank logs and help, and Benox50 for another bugfix (see update log below).

UPDATE 1-11-2020: You also no longer take heat damage during reserves! Still no freespace used.

UPDATE 3-17-2020: Thanks to Benox50, this patch now prevents a crash that can result from pausing the game on that same frame that auto reserve tanks activate. Also renamed this patch because it's now more of a general bugfix; if you have any further suggestions for bugs that can be fixed about reserves, let us know in the metconst discord!

UPDATE 5-17-2022: Reserve tanks now come full.
Reserve tanks also do not empty themselves out if not all of their contents were used to heal Samus during auto or manual refill. Also fixed that weird jank where if you start manually refilling, deselect, and reselect the option, the manual refill will continue. You can now also press A at any time during manual refill to stop. No freespace used.