invoke log util, console.log can be switched off

lib/log.js

@@ -0,0 +1,17 @@
+var ifPrint = true;
+
+function setPrintStatus(status){
+	ifPrint = !!status;
+}
+
+function printLog(content,type){
+	if(!ifPrint) return;
+
+	var tip = content;
+	console.log(tip);
+}
+
+module.exports.printLog       = printLog;
+module.exports.setPrintStatus = setPrintStatus;
+module.exports.T_TIP          = 0;
+module.exports.T_ERR          = 1;