+/**
+ * Send a message to "target mask" target(s).
+ *
+ * See RFC 2812, sec. 3.3.1 for details.
+ *
+ * @param from The client from which this command has been received.
+ * @param command The command to use (PRIVMSG, NOTICE, ...).
+ * @param targetMask The "target mask" (will be verified by this function).
+ * @param message The message to send.
+ * @param SendErrors Whether to report errors back to the client or not.
+ * @return CONNECTED or DISCONNECTED.
+ */