* Upgrade wagon-ssh to 3.2.0
* Upgrade maven-jxr-plugin to 3.0.0
* Upgrade maven-shade-plugin to 3.2.0
* Upgrade jacoco-maven-plugin to 0.8.2
* Upgrade maven-project-info-reports-plugin to 3.0.0
* Upgrade maven-enforcer-plugin to 3.0.0-M2
* Upgrade maven surefire plugins to 2.22.0
* Ensure same version of maven-surefire-plugin and maven-surefire-report-plugin
* FS: Remove the gitprefix logic
* SystemReader: Use discoverGitSystemConfig() in openSystemConfig()
* FS: Add a method to discover the system-wide config file
* FS: Extend readPipe() to optionally take additional environment
* FS: Document readpipe()'s encoding parameter
* Split discoverGitPrefix() code out into discoverGitExe()
* Equalize discoverGitPrefix() implementations between POSIX and Win32
* Move resolveGrandparentFile() to the base class for wider use
* Revert "Add a method to DfsOutputStream to read as an InputStream"
* Add a Merger.merge method that makes flushing optional
* Teach mergers to use ObjectInserter.newReader()
* Add a method to ObjectInserter to read back inserted objects