Add pear modules, mail and net_smtp via composer (#93)

Add pear modules, mail and net_smtp via composer, remove php 5.6 build due to phpunit 6

lib/composer/vendor/sebastian/comparator/ChangeLog.md

@@ -0,0 +1,19 @@
+# ChangeLog
+
+All notable changes are documented in this file using the [Keep a CHANGELOG](http://keepachangelog.com/) principles.
+
+## [2.1.1] - 2017-12-22
+
+### Fixed
+
+* Fixed [phpunit/#2923](https://github.com/sebastianbergmann/phpunit/issues/2923): Unexpected failed date matching
+
+## [2.1.0] - 2017-11-03
+
+### Added
+
+* Added `SebastianBergmann\Comparator\Factory::reset()` to unregister all non-default comparators
+* Added support for `phpunit/phpunit-mock-objects` version `^5.0`
+
+[2.1.1]: https://github.com/sebastianbergmann/comparator/compare/2.1.0...2.1.1
+[2.1.0]: https://github.com/sebastianbergmann/comparator/compare/2.0.2...2.1.0