Add missing parameters to submit hook

The submit hook takes --change and --submitter-username arguments. Add
these to the documentation.

Change-Id: I1dd350e2ef526a1dd375c9ee5bde11f5558c4022

src/main/resources/Documentation/hooks.md

diff --git a/src/main/resources/Documentation/hooks.md b/src/main/resources/Documentation/hooks.md
index 16bbc46..4429fb4 100644
--- a/src/main/resources/Documentation/hooks.md
+++ b/src/main/resources/Documentation/hooks.md
@@ -49,7 +49,7 @@
 output from the hook will be returned to the user.
 
 ```
-  submit --project <project name> --branch <branch> --submitter <submitter> --patchset <patchset id> --commit <sha1>
+  submit --change <change id> --project <project name> --branch <branch> --submitter <submitter> --submitter-username <username> --patchset <patchset id> --commit <sha1>
 ```
 
 ## Asynchronous Hooks