Fixing an issue with the PHP versions

Travis was saying PHP 5.3.3 and the composer.json file had >= 5.3.4
Fixing filename case issue

Mac OS X is case-insensitive by default and there was a typo in the
inclusion of the OAuth class
Adding a build status image
Lowering the minimum PHP version to 5.3.3
Merge pull request #3 from rudisimo/hotfix/travis-fix

Travis-CI Fix