MCInstance Loader

Here is a surprise update before christmas :D Most of the additions were done by @DrParadox7 on Github via a pull request.

Feature changes and fixes

• Added sided overrides, you can now create a client-overrides or a server-overrides folder that contains files to override only when on a specific side. (This feature was initially planned for 3.0)
• The server will now shutdown correctly after the mcinstance file has been installed or when the installation has failed.
• Fixed the mod deleting subfolders in the mods folder, as it thought those were always empty.
• Reworked the logs when on a server, servers now clearly see when a mod gets downloaded and that the server restarts and doesn't crash.

Technical changes

• Bumped the version number to 2.5
• IOExceptions from the WebHelper class will also print their stack trace
• IOExceptions from the FileHelper class won't get printed twice anymore