Refactor NetworkRequest class

Add followUser and unfollowUser methods to TwitchAccount

src/common/NetworkCommon.hpp

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <functional>
+
+class QNetworkReply;
+
+namespace chatterino {
+
+class NetworkResult;
+
+using NetworkSuccessCallback = std::function<bool(NetworkResult)>;
+using NetworkErrorCallback = std::function<bool(int)>;
+using NetworkReplyCreatedCallback = std::function<void(QNetworkReply *)>;
+
+enum class NetworkRequestType {
+    Get,
+    Post,
+    Put,
+    Delete,
+};
+
+}  // namespace chatterino