Merge branch 'stable-4.5' into stable-4.6

* stable-4.5:
  Prepare 4.5.6-SNAPSHOT builds
  JGit v4.5.5.201812240535-r
  Call AdvertiseRefsHook before validating wants

Change-Id: I0fd67ddd9c4966c20d82cdfe78b2f9d4898b4665
Signed-off-by: Jonathan Nieder <jrn@google.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

diff --cc org.eclipse.jgit/src/org/eclipse/jgit/transport/UploadPack.java
Simple merge