Update README

README.md

@@ -223,7 +223,7 @@ You can use the `-t` or `--template` flag on the dotenv cli to create a template
 ```shell
 $ dotenv -t .env
 ```
-A template will be created in your working directory named `{FINAME}.template`. So in the above example, it would create a `.env.template` file. 
+A template will be created in your working directory named `{FINAME}.template`. So in the above example, it would create a `.env.template` file.
 
 The template will contain all the environment variables in your `.env` file but with their values set to the variable names.
 
@@ -233,7 +233,7 @@ S3_BUCKET=YOURS3BUCKET
 SECRET_KEY=YOURSECRETKEYGOESHERE
 ```
 
-Would become 
+Would become
 
 ```shell
 # .env.template
@@ -247,6 +247,11 @@ Personally, I prefer to commit the `.env` file with development-only settings. T
 
 By default, it **won't** overwrite existing environment variables as dotenv assumes the deployment environment has more knowledge about configuration than the application does. To overwrite existing environment variables you can use `Dotenv.overload`.
 
+You can use the `-o` or `--overload` flag on the dotenv cli to override existing `ENV` variables.
+```shell
+$ dotenv -o -f ".env.local,.env"
+```
+
 ## Contributing
 
 If you want a better idea of how dotenv works, check out the [Ruby Rogues Code Reading of dotenv](https://www.youtube.com/watch?v=lKmY_0uY86s).