Added Travis CI configuration.
Updated phpunit's configuration files to use best practices.
Fixed undefined variables.
Refactored namespaces of Dumpers, Highlighters and some Messages.
Removed default StartMessage on Debug::enable().
Suggested xhprof extension in composer.json.
Remove Singleton from Debug.
Fixed bracket typo in function call.
Moved skip properties option from Debug to ObjectDumper.
Removed Debug dependency from IDumperManager.
Replace string concatenation for array implode during variable dumps.
Moved DumpMessage back to Message namespace.
Moved DumperManager and Dumpers back to Debug namespace.
Refactored DumperManager and updated documentation.
Cleaning up dependencies.