Merge branch 'master' into stable-5.0

* master:
  DescribeCommand: Refactor to not use deprecated Repository#peel
  Repository: Deprecate #peel method
  Repository: Make #exactRef and #findRef final
  Skip ignored directories in FileTreeIterator
  Repository: Deprecate getTags method
  InfoRefsServlet: Refactor to not use deprecated methods
  RefAdvertiser: Add send(Collection<Ref>) and deprecate send(Map<String, Ref>)
  Remove deprecated Repository#notifyIndexChanged
  Implementors should override Repository#notifyIndexChanged(boolean)
  Revive Repository#notifyIndexChanged()
  Remove further unnecessary 'final' keywords
  Execute AdvertiseRefsHook only for protocol v0 and v1
  Add protocol v2 support in "jgit daemon"
  Teach UploadPack "ofs-delta" in "fetch"
  Teach UploadPack "include-tag" in "fetch"
  Avoid using #refs in UploadPack#sendPack
  FileRepository: Don't use deprecated RefDatabase#getRefs(String)
  BatchRefUpdate: Don't use deprecated RefDatabase#getRefs(String)

Change-Id: I16c5da62d09262d3f4070aa0f466dd6c8352b5ea
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>