updage help message

const.go

@@ -11,15 +11,15 @@ const (
 
 // Message has message strings.
 var Message = map[string]string{
-	"commandDescription": "A command to format Android Logcat",
+	"commandDescription": "A command line tool for format Android Logcat",
 	"helpFormat": `Format of output
  - Available keyword:
      %t (%time), %a (%tag), %p (%priority)
      %i (%pid), %I (%tid), %m (%message)
  - Example:
    adb logcat -v time | logcatf "%t %4i %m"
-   adb logcat -v threadtime | logcatf "%t, %a, %m" > logcat.csv
-   adb logcat -v threadtime | logcatf "%t" -o "Exception" -c "adb shell screencap -p /data/local/tmp/screen.png"
+   adb logcat -v threadtime | logcatf "%t, %a, %m" --to-csv > logcat.csv
+   adb logcat -v | logcatf -o "Exception" -c "adb shell screencap -p /data/local/tmp/s.png"
  - Default Format:
    "%time %tag %priority %message"`,
 	"helpTrigger":           "regex to trigger a COMMAND.",