update README.md

README.md

@@ -7,13 +7,6 @@ An extensible and powerful go configuration manager, which is inspired by [oslo.
 $ go get -u github.com/xgfone/gconf/v5
 ```
 
-### V3
-```shell
-$ go1.x  get -u github.com/xgfone/gconf
-$ go1.11 get -u github.com/xgfone/[email protected]
-$ go1.12 get -u github.com/xgfone/[email protected]
-$ GONOSUMDB="*" go1.13 get -u github.com/xgfone/[email protected]
-```
 
 ## Goal
 
@@ -30,6 +23,7 @@ Source is used to read the configuration data. You can load lots of sources to r
 
 **Notice:** If the source supports the watcher, it will add it to watch the changed of the source data automatically.
 
+
 ## Decoder
 
 The source reads the original data, that's `[]byte`, and it must be decoded. The default has implemented the `json`, `yaml`, `toml` and `INI` decoders.