Disable dependency libraries

[hiulit]

I've created a new SteamDependencyLibraries class to enable/disable the dependency libraries, so they won't be compiled when "Steam integration" is disabled.

Basically, what it does, is when the user clicks on the "Disable Steam Integration" checkbox, it creates backups of all the .gdns and .gdnlib, and then removes stuff from the originals so the dependency libraries won't be compiled.
When the user enables the Steam Integration, all those files are reverted back to its originals.

As a little bonus, I've fixed an issue. When the "Steam integration" is disabled and the user disables the plugin, the disabled state stays and when the user enables back the plugin it still disabled. I made it so it is enabled when the plugin is enabled.

[samsface]

@hiulit I'm not getting the problem you have?

Is it you don't want the dlls to be exported when steam integration is disabled?

[hiulit]

Exactly! When Steam Integration is disabled, I don't want the dlls to be compiled/copied.
I saw an issue that some people also wanted that as well.

[samsface]

Ok seems like a good feature. Will checkout your change and try soon 🔜

[AdriaandeJongh]

This is a great PR – especially for multi-platform games. Hoping it'll make it in!