Merge branch 'stable-4.9' into stable-4.10

Merge branch 'stable-4.9' into stable-4.10

* stable-4.9:
  Prepare 4.9.8-SNAPSHOT builds
  JGit v4.9.7.201810191756-r
  Update API problem filter
  Prepare 4.7.7-SNAPSHOT builds
  JGit v4.7.6.201810191618-r
  Update API problem filter
  Fix file handle leak in ObjectDownloadListener.onWritePossible
  Replace Findbugs with Spotbugs in org.eclipse.jgit/pom.xml
  Replace FindBugs with SpotBugs
  Prepare 4.4.2-SNAPSHOT builds
  JGit v4.0.3.201509231615-r

Change-Id: I6f07ea02491ba3a32f30ee2408e1153241cc8a07
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>