Update readme

README.md

@@ -36,7 +36,7 @@ OR
 npm install -g backport
 ```
 
-After installation you must update the global config in `~/.backport/config` with your Github username and a Github access token. More info [here](https://github.com/sqren/backport/blob/master/docs/getting-started.md#new-user-create-user-config)
+After installation you must update the global config in `~/.backport/config.json` with your Github username and a Github access token. More info [here](https://github.com/sqren/backport/blob/master/docs/getting-started.md#new-user-create-user-config)
 
 ## Run via Docker
 
@@ -45,13 +45,18 @@ The easiest way is to add the following to your bash profile, and update `BACKPO
 
 ```sh
 backport() {
-    BACKPORT_FOLDER=~/.backport
-    GITCONFIG=~/.gitconfig
+    BACKPORT_CONFIG_DIR=~/.backport
+    GIT_CONFIG_FILE=~/.gitconfig
 
-    docker run -it --rm -v $(pwd):/app:ro -v $BACKPORT_FOLDER:/root/.backport -v $GITCONFIG:/etc/gitconfig sqren/backport "$@"
+    docker run -it --rm -v $(pwd):/app:ro -v $BACKPORT_CONFIG_DIR:/root/.backport -v $GIT_CONFIG_FILE:/etc/gitconfig sqren/backport "$@"
 }
 ```
 
+Where:
+
+- `BACKPORT_CONFIG_DIR`: This can be ANY empty folder on your local machine. Upon running the docker container for the first time, a `config.json` will be created inside automatically. This must be filled out with `username` and `accessToken` or these must be passed as CLI arguments: `backport --username <username> --accessToken <accessToken>`
+- `GIT_CONFIG_FILE`: Must point to a local `.gitconfig` file that contains the user's name and email.
+
 You can now use `backport` as if it was installed locally.
 
 ## Usage