README: Add better examples

Since the examples are likely to be copy/pasted into various configs,
add cros format and pass the --commit flag to cros lint.

BUG=None
TEST=None

Change-Id: Ib22383bd877bb201979a4ccba78667ceee4a444d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/repohooks/+/4418891
Auto-Submit: Jeremy Bettis <jbettis@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Jeremy Bettis <jbettis@chromium.org>
diff --git a/README.md b/README.md
index 8c0904f..28cba0a 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,8 @@
 # https://chromium.googlesource.com/chromiumos/repohooks/
 
 [Hook Scripts]
-cros lint = cros lint ${PRESUBMIT_FILES}
+cros format = cros format --check --commit ${PRESUBMIT_COMMIT} ${PRESUBMIT_FILES}
+cros lint = cros lint --commit ${PRESUBMIT_COMMIT} ${PRESUBMIT_FILES}
 
 [Hook Overrides]
 cros_license_check: true