v4.0.0

Refactored entire project to use type declarations everywhere. Because of that, the minimum supported PHP version is now
PHP 7.4.

Complete list of changes: 3.x...v4

High Impact Changes

• Removed VideoDetails class. We use VideoInfo class in its place
• DownloadOptions::getVideoInfo() will now return VideoInfo class
• AbstractModel class has been renamed to JsonObject
• PlayerResponseParser class has been renamed to SignatureLinkParser, and its parseLinks method has a different signature

Low Impact Changes

• removed SplitStream class
• removed DownloadOptions::getSplitFormats method
• SignatureDecoder::parseFunctionName and SignatureDecoder::parseFunctionCode are protected methods now