Merge pull request #25 from miccheng/master

Updates to configs.
Merge pull request #26 from miccheng/master

Fix scope of config_file attribute. Add new config interface class.
Merge pull request #27 from miccheng/master

Fix inclusion bug.
Merge pull request #28 from miccheng/master

Change name of log file.
Merge pull request #29 from miccheng/master

Add Daemon class as part of the core framework.
Fix fatal error in PHP 5.4
Do not raise error if user call Backend::get($id) with $id equals null.
Update PDO.php

Remove old code.
Update PDO.php
Update PDOTest.php

Test for PHPQueue\Backend\PDO::get() with null input.
Update README.md

Update Travis link/static icon.
Update .travis.yml

Add '--coverage-text', simple option to let PHPUnit report coverage in basic text format.
Merge pull request #32 from andytruong/pr/travis

Update Travis info
Merge pull request #34 from andytruong/pr/travis-text-coverage

Travis: Use '--coverage-text' option
Merge pull request #30 from andytruong/pr/backend-pdo

Some issues with PDO backend