add WebSocketsVersion.h and some build checks

src/WebSocketsVersion.h

@@ -0,0 +1,36 @@
+/**
+ * @file WebSocketsVersion.h
+ * @date 07.01.2021
+ * @author Markus Sattler
+ * 
+ * Copyright (c) 2015 Markus Sattler. All rights reserved.
+ * This file is part of the WebSockets for Arduino.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#ifndef WEBSOCKETSVERSION_H_
+#define WEBSOCKETSVERSION_H_
+
+#define WEBSOCKETS_VERSION "2.3.2"
+
+#define WEBSOCKETS_VERSION_MAJOR 2
+#define WEBSOCKETS_VERSION_MINOR 3
+#define WEBSOCKETS_VERSION_PATCH 2
+
+#define WEBSOCKETS_VERSION_INT 2003002
+
+#endif /* WEBSOCKETSVERSION_H_ */