Add human-readbale log output (#681)

Add human-readable log output. It prints out the exact source code line information.

formatter/set.go

@@ -0,0 +1,10 @@
+package formatter
+
+import "github.com/sirupsen/logrus"
+
+// SetTextFormatter set the formatter for given logger.
+func SetTextFormatter(logger *logrus.Logger) {
+	logger.Formatter = NewTextFormatter()
+	logger.ReportCaller = true
+	logger.AddHook(NewContextHook())
+}