Update to cinnamon theme 5.8

[Initu-Castilhos]

Update to cinnamon theme 5.8

[axel358]

Expanding on this, add support for the new events Panel on Cinnamon calendar applet and maybe improve Cinnamon dialogs to use a single color like in Mint Y theme or like gnome shell dialogs

[ghost]

I'd like to politely throw my support behind this too. I really like this theme and would love to use it on modern Cinnamon.

[axel358]

While we wait for Matcha to add support for newer Cinnamon versions i sorta made a half decent mix of Mint Y theme with Matcha Sea colors, though about sharing it here in case anyone else finds it useful https://github.com/axel358/cinnamon-mint-y-sea