Merge branch '5.5' into 5.6

Author: sebastianbergmann

ChangeLog-4.8.md

@@ -2,6 +2,12 @@
 
 All notable changes of the PHPUnit 4.8 release series are documented in this file using the [Keep a CHANGELOG](http://keepachangelog.com/) principles.
 
+## [4.8.28] - 2016-11-14
+
+### Fixed
+
+* Improved the fix for [#1955](https://github.com/sebastianbergmann/phpunit/issues/1955): Process isolation fails when running tests with `phpdbg -qrr`
+
 ## [4.8.27] - 2016-07-21
 
 ### Fixed