Merge branch 'stable-6.1' into stable-6.2

* stable-6.1:
  UploadPack: don't prematurely terminate timer in case of error
  Do not create reflog for remote tracking branches during clone
  UploadPack: do not check reachability of visible SHA1s
  Add missing package import javax.management to org.eclipse.jgit

Change-Id: Ib3ff6a038e1b92a931a7f2624c19bbefd8cb95fd

diff --cc org.eclipse.jgit.test/tst/org/eclipse/jgit/api/FetchCommandTest.java
Simple merge

diff --cc org.eclipse.jgit/META-INF/MANIFEST.MF
Simple merge

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