Merge pull request #6 from wnasich/master

Add a timestamp at beginning of each error message before send to log
Allowing to test scheduled jobs through a scheduled ping
Fixing variable name.
Merge pull request #7 from KyHikari/master

Fixing variable name.
Removing unneeded composer requirement
Adding composer installers
Adding ability to retry jobs, and going PSR compliant
BC change: by default do not save job status. You can still enable this with the option 'saveJobStatus' in the 'redis' configuration
Changing loop conditions in order to avoid an access to undef array offset