Feature Request: Add version-agnostic commands to install Godot

[donovani]

With NVM, you have access to version-agnostic commands:

• nvm install - Reads NVM version from .nvmrc file and installs it
• nvm use - Reads NVM version from .nvmrc file and swaps to it

This is really useful because you can define the version you want in a file then load it based on that value. When someone pulls the project for the first time, they don't need to know what exact version of Node to use, it's just there. It also means that if runtime versions change, it's incredibly easy to update your local environment.

I think GodotEnv should have similar commands.

• godotenv godot install - Reads Godot version from file and installs it
• godotenv godot use - Reads Godot version from file and swaps to it

I can see a few different ways that this version information could be stored

1. It reads the Godot version from the project.godot file
2. It reads the Godot SDK version from the .csproj file
3. It stores it in the top level of addons.json
4. It stores in a new .godotrc file

With this, the end goal would be that someone could clone any Godot project and run a single command to install the correct editor version without needing to look through files to know the correct one to install on that specific commit.

EDIT: A workaround in the meantime for those who are also looking for this: godotenv godot install $(cat .godotrc). Just make your own .godotrc file.