[ticket/11513] Add PHPUnit 3.7 and DbUnit 1.2 as a composer dev dependency.

PHPBB3-11513
[ticket/11513] Update (all) composer dependencies.

PHPBB3-11513
[ticket/11513] Use PHPUnit from composer in .travis.yml.

PHPBB3-11513
[ticket/11513] Update all CLI calls to phpunit to use vendor/bin.

PHPBB3-11513
[ticket/11513] Update RUNNING_TESTS.txt to no longer refer to PEAR.

PHPBB3-11513
Merge pull request #1387 from bantu/ticket/11513

[ticket/11513] Install PHPUnit via Composer