docs: update README

Signed-off-by: Leonardo Di Donato <leodidonato@gmail.com>

README.md

@@ -14,14 +14,16 @@ This is the CLI.
 
 ```console
 Usage of ./bin/maintainers-generator:
-  -app-id string
-        ID of the GitHub app. If set, requires --app-private-key path to be set and --github-token-path to be unset.
-  -app-private-key-path string
-        Path to the private key of the github app. If set, requires --app-id to bet set and --github-token-path to be unset
+  -banner
+        Whether you want a header on top of the output YAML maintainers file
   -dedupe
         Whether to dedupe or not sub-project areas for every maintainer. (default true)
   -dry-run
-        Dry run for testing (uses API tokens but does not mutate). (default true)
+        Dry run for testing (uses API tokens but does not mutate).
+  -github-app-id string
+        ID of the GitHub app. If set, requires --github-app-private-key-path to be set and --github-token-path to be unset.
+  -github-app-private-key-path string
+        Path to the private key of the github app. If set, requires --github-app-id to bet set and --github-token-path to be unset
   -github-endpoint value
         GitHub's API endpoint (may differ for enterprise). (default https://api.github.com)
   -github-graphql-endpoint string
@@ -30,12 +32,12 @@ Usage of ./bin/maintainers-generator:
         GitHub's default host (may differ for enterprise) (default "github.com")
   -github-token-path string
         Path to the file containing the GitHub OAuth secret.
-  -hmac string
-        Path to the file containing the GitHub HMAC secret. (default "/etc/webhook/hmac")
   -log-level string
         Log level. (default "info")
   -org string
         The GitHub organization name.
+  -output string
+        The path where to write the output YAML maintainers (default "stdout")
   -persons-db string
         The path to a JSON file containing handle => name/company mappings (default "data/data.json")
   -repo string
@@ -52,7 +54,7 @@ For example, you could run:
 ./bin/maintainers-generator --github-token-path /etc/token --org falcosecurity
 ```
 
-Which will output a YAML like:
+Which will output a YAML to STDOUT like the following one:
 
 ```yaml
 - name: user1