* Prepare 5.1.17-SNAPSHOT builds

* [releng] Enable japicmp for the fragments added in 5.8.0

* server: Add a custom error handler
* transport: Add methods that do not handle exceptions
* transport: Let users specify an error handler for unpacking a pack file
* ReceivePack: Use try-with-resources for PostReceiveHook
* transport: Consolidate status reporting code
* transport: Add ReceiveCommandErrorHandler
* transport: Move exception handler to the caller
* transport: Move handling code to the caller side

* Add missing braces in CherryPickCommand

* Upgrade maven-javadoc-plugin to 3.1.1
* Upgrade ecj to 3.18.0
* Upgrade wagon-ssh to 3.3.3

* Enable cloning only specific tags

* pgm: Handle IOException in Version command
* pgm: Fix missing braces in UploadPack.run()
* pgm: Handle IOException in UploadPack command
* pgm: Handle exceptions in Tag command
* pgm: Fix missing braces in Status.run()
* pgm: Handle exceptions in Status command
* pgm: Fix missing braces in ShowRef.run()
* pgm: Handle IOException in ShowRef command
* pgm: Fix missing braces in Show.run()
* pgm: Handle exceptions in Show command
* pgm: Fix missing braces in Rm command
* pgm: Handle GitAPIException in Rm command
* pgm: Handle exceptions in RevParse command
* pgm: Externalize error message

* Move BaseReceivePack#advertisedRefs getter and setter to ReceivePack
* Move BaseReceivePack#walk getter to ReceivePack
* Move BaseReceivePack#db getter to ReceivePack
* Move BaseReceivePack#pushCert getter and setter to ReceivePack
* Remove unused API problem filters

* Enable japicmp for new SSH bundle; update its baseline

* New GpgConfig for typed access to GPG settings

* UploadPack: Remove redundant specification of type
* Upgrade spotbugs to 3.1.6

* JGit v5.0.0.201806131550-r

* Fix Javadoc typo

* Allow overriding DfsPackDescription comparator for scanning packs
* Move DfsPackDescription comparators to common location
* Use Comparators for PackSource
* DfsPackDescription: Disallow null PackSource

* Repository: Make #exactRef and #findRef final

* Merge branch 'stable-4.9' into stable-4.10

* ConfigTest: Add some additional comment parsing tests
* Config: Drop backslash in invalid escape sequences in subsections
* Config: Match C git behavior more closely in escaping values

* UntrackedFilesHandler: Fix non-localized string
* Main: Replace deprecated ExampleMode with OptionHandlerFilter
* ObjectCheckerTest: Factor duplicate instances out to constants
* SubmoduleConfigTest: Add additional tests in fetchRecurseToConfigValue
* SubmoduleConfig: Simplify #toConfigValue

* [infer] Fix resource leak in RepoCommand

* JGit v4.5.0.201609210915-r

* Fix TreeWalk to reset attributes cache for each entry

* Remove unused package export from bundle org.eclipse.jgit.lfs.test

* smart HTTP server: Pass along "want X not valid" to client

* Silence Maven complaining about unset versions of reporting plugins

* Update Jetty to 9.2.13.v20150730

* Treat CloneCommand.setBranch(null) as setBranch("HEAD")
* Treat CloneCommand.setRemote(null) as setRemote("origin")
* Document CloneCommand.setURI(null)
* Handle null in ProgressMonitor setters
* Document CloneCommand.setDirectory(null) and setGitDir(null) more clearly

* Merge remote-tracking branch 'origin/stable-3.6'

* Fix AnyObjectId's generic type declaration of Comparable

* Delete the iplog generator, cont'd

* Update last jgit release version used in clirr API checks
* Update maven plugin versions