ReceiveCommits: uniformize commit validation error messages.
Before
[abcdabc] missing subject; Change-Id must be in commit message
footer
After
commit abcdabc: missing subject; Change-Id must be in message
footer
Change-Id: I15ca67fb591b0d237cb9217936853ec8dc706aaa
diff --git a/Documentation/error-missing-subject.txt b/Documentation/error-missing-subject.txt
index 3703ade..6ef37a4 100644
--- a/Documentation/error-missing-subject.txt
+++ b/Documentation/error-missing-subject.txt
@@ -1,4 +1,4 @@
-= missing subject; Change-Id must be in commit message footer
+= commit xxxxxxx: missing subject; Change-Id must be in message footer
With this error message Gerrit rejects to push a commit to a project
which is configured to always require a Change-Id in the commit