Change LICENSE.md to MIT/Expat

[Spartan322]

Update COPYRIGHT to remove GPL 3.0 license

[FakeByte]

Can you change it MIT License? I know the too are identical but with the license text in LICENSE.md saying MIT I think its nicer if the names we use match

[Spartan322]

That's ill advised by the debian COPYRIGHT format because calling a license MIT without a variant name is technically ambiguous and this is a technical file. (aside from it being kinda standard for the format) There is no one "MIT" which is the problem, whereas there is only one Expat which is MIT. Also calling it Expat means it matches Godot which means we don't copy the license text twice for OpenVicProject/OpenVic#711.

[FakeByte]

I didnt notice the change in OpenVicProject/OpenVic#711, I think that should also be renamed to MIT License, thats how everyone calls it today, nobody these days calls it Expat license anymore, thats why there is no ambiguity.

From the debian docs you shared:
"For SPDX compatibility, versions with trailing dot-zeroes are considered to be equivalent to versions without (e.g., “2.0.0” is considered equal to “2.0” and “2”).

Currently, the full text of the licenses is only available in the SPDX Open Source License Registry."

This means even debian tries to stay SPDX compatible and instead of maintaining a full license list they refer to SPDX which is basically used by everyone. SPDX doesnt list an Expat license at all, it only list the MIT License with the SPDX identifier MIT. Thats what everyone uses, github auto checks the license file and will show our project as MIT License, our license itself calls itself MIT License,

If you check the Open Source Initiative they also call it MIT License (and also refer to SPDX)
https://opensource.org/license/MIT

We should just follow modern standard and call it MIT

[FakeByte]

This should be 2023 - present