Add info about repo launcher 1.22

Change-Id: I9121894ba8efe530ec995706b019460a33cc1c2c
diff --git a/src/source/downloading.jd b/src/source/downloading.jd
index ee65cbb..6ed0004 100644
--- a/src/source/downloading.jd
+++ b/src/source/downloading.jd
@@ -72,6 +72,9 @@
 <p>
   For version 1.21, the SHA-1 checksum for repo is b8bd1804f432ecf1bab730949c82b93b0fc5fede
 </p>
+<p>
+  For version 1.22, the SHA-1 checksum for repo is da0514e484f74648a890c0467d61ca415379f791
+</p>
 <h2 id="initializing-a-repo-client">
   Initializing a Repo client
 </h2>