Allow SetReviewersCommand to accept a commit hash as argument

Since: Id36abd485ee84b2ae4b2eef2ff0065e675cd1b2f the command has lost
the ability for callers to specify a commit SHA-1 as an argument. Now
that the class uses InternalChangeQuery for change lookup, it is
possible to support searching commit SHA-1's again.

Change-Id: I7530cd6044eb7cc0d6754cffd8bac69f99494445
diff --git a/Documentation/cmd-set-reviewers.txt b/Documentation/cmd-set-reviewers.txt
index 0a757fd..f8a272d 100644
--- a/Documentation/cmd-set-reviewers.txt
+++ b/Documentation/cmd-set-reviewers.txt
@@ -20,7 +20,7 @@
 
 Changes can be specified in the
 link:rest-api-changes.html#change-id[same format] supported by the REST
-API.
+API, as well as with the commit SHA-1.
 
 == OPTIONS
 
@@ -77,6 +77,13 @@
 	  Iac6b2ac2
 ----
 
+Add all project owners as reviewers to commit 13dff08acca571b22542ebd2e31acf4572ea0b86.
+----
+	$ ssh -p 29418 review.example.com gerrit set-reviewers \
+	  -a "'Project Owners'" \
+	  13dff08acca571b22542ebd2e31acf4572ea0b86
+----
+
 GERRIT
 ------
 Part of link:index.html[Gerrit Code Review]