Removes explicit PHPUnit call from .travis.yml
Adds PHP-Bench to Composer dev requirements.

When composer is run with `--dev` PHP-Bench will be installed as well.
Merge pull request #37 from potherca/master

Removes explicit PHPUnit call from .travis.yml
Merge pull request #38 from potherca/develop

Adds PHP-Bench to Composer dev requirements.
Merge remote-tracking branch 'origin/master' into SetterInjection
#34 Setter injection - Additional tests