Limited clipboard size to 1kb when SSL is enabled #4601

@XinyuHou I had no choice but to block clipboard data over 1kb in
size... anything over that and you get an access violation.

src/lib/server/Server.cpp

@@ -2389,3 +2389,9 @@ Server::dragInfoReceived(UInt32 fileNum, String content)
 
 	m_screen->startDraggingFiles(m_dragFileList);
 }
+
+bool
+Server::isSecure() const
+{
+	return m_clientListener->isSecure();
+}