docs: optimize readme

Author: guobinhit

README.md

@@ -11,20 +11,6 @@ If you see a problem that you'd like to see fixed, the best way to make it happe
 
 You can also ask for problem-solving ideas and discuss in GitHub issues directly.
 
-# INDEX
-
-- [Overview](#overview)
-- [Usage](#usage)
-
-# Overview
-
-In specified package, provides some practical util, as below:
-
-- `format`: format a `time` value to `string`, such as `GetYyyyMmDdHhMmSs`,
-- `parse`: parse a `string` value to `time`, such as `GetYyyyMmDdHhMmSs`.
-
-A time toolkit written in Go.
-
 # Usage
 
 Firstly, download this pkg,
@@ -38,8 +24,6 @@ Secondly, use it.
 ```go
 import (
     "github.com/guobinhit/auxo"
-    "github.com/guobinhit/auxo/format"
-    "github.com/guobinhit/auxo/parse"
 )
 
 // Get a specified time by add days, such as d is 2022-04-13 10:20:30 and days is 10,
@@ -48,16 +32,16 @@ aDate := auxo.GetTimeAddDays(time.Now(), 10)
 
 // Get a specified date format time string of common version, such as d is 2022-04-13 10:20:30,
 // then aString is "2022-04-23 10:20:30"
-aString := format.GetYyyyMmDdHhMmSs(time.Now())
+aString := auxo.FormatYyyyMmDdHhMmSs(time.Now())
 
 // Get a specified date format time string of china version, such as d is 2022-04-13 10:20:30,
-// then aString2 is "2022年04月23日 10:20:30", like GetCnOfYyyyMmDdHhMmSs method, 
-// GetEnOfYyyyMmDdHhMmSs return "2022/04/23 10:20:30" and GetCptOfYyyyMmDdHhMmSs return "20220423102030".
-aString2 := format.GetCnOfYyyyMmDdHhMmSs(time.Now())
+// then aString2 is "2022年04月23日 10:20:30", like FormatCnOfYyyyMmDdHhMmSs method, 
+// FormatEnOfYyyyMmDdHhMmSs return "2022/04/23 10:20:30" and FormatCptOfYyyyMmDdHhMmSs return "20220423102030".
+aString2 := auxo.FormatCnOfYyyyMmDdHhMmSs(time.Now())
 
 // Get a specified date format time, such as dStr is "2022-04-13 10:20:30",
 // then aTime is 2022-04-23 10:20:30
-aTime, err := parse.GetYyyyMmDdHhMmSs("2022-04-13 10:20:30")
+aTime, err := auxo.ParseYyyyMmDdHhMmSs("2022-04-13 10:20:30")
 ```
 
 Finally, good luck guys!