Update git submodules

* Update plugins/replication from branch 'stable-2.16'
  to 4ee733142ac71556705df02cdab396b804463879
  - PushOne: Improve format of log of references to be pushed
    
    The references to be pushed are logged by just passing the list
    of RemoteRefUpdate instances to the logger. This results in the
    List's default implementation of toString() being called, which
    renders each object in a comma-separated list.
    
    Each object is rendered by RemoteRefUpdate's toString() method
    which includes some fields that are not relevant here, or omits
    some information that might be useful. For example:
    
      [RemoteRefUpdate[remoteName=refs/meta/config, NOT_ATTEMPTED,
      (null)...a7038eb8827cfd29cb3fca335e882f4d5ed09b62, srcRef=refs/meta/config,
      forceUpdate, message=null]
    
    - The 'remoteName' is the name on the destination. In this case it's
      the same as 'srcRef' but could be different if replication has been
      configured to push to a different refname. It is potentially confusing
      to have them not logged next to each other.
    - '(null)...a7038eb8827cfd29cb3fca335e882f4d5ed09b62' shows the old
      and new IDs; this is in the standard git ref update format aside
      from '(null)' which is shown instead of zeros.
    - 'forceUpdate' is only included when true; this is the same for
      the 'fastForward' field.
    - the update has a flag indicating if it's a delete, but this is
      not included in the output at all.
    - 'message' is always null for udates by replication so it's not
      necessary to include in the log.
    
    Add a custom method to format the refs for logging, with the information
    presented in a clearer way. Continue to log it on a single line, comma-
    separated. This might not be ideal for human readers, but makes it easier
    when processing the logs with grep or any other tool.
    
    With this change, the logged information looks like:
    
      RemoteRefUpdate{refSpec=refs/meta/config:refs/meta/config,
      status=NOT_ATTEMPTED, id=(null)..a7038eb8827cfd29cb3fca335e882f4d5ed09b62
      force=yes, delete=no, ffwd=no}
    
    Now the irrelevant information (message) is removed, missing information
    (delete) is added, and the source and destination refs are presented in
    a single "refSpec" field.
    
    Change-Id: Idd153daf44cd79a0920ea0b72c64ea58d0926f59
    

plugins/replication

diff --git a/plugins/replication b/plugins/replication
index 937b403..4ee7331 160000
--- a/plugins/replication
+++ b/plugins/replication
@@ -1 +1 @@
-Subproject commit 937b403a596d48d01f5fc1ce380b6d6558cb6051
+Subproject commit 4ee733142ac71556705df02cdab396b804463879