Move default value to collector itself from fatory

More over, it fixes a bug if user use factory without options,
because factory send null instead of nothing which break everythinh.

And then, it make the collecter easier to re-use
Added graphite to factory
Fixed README.md
[Bundle] Removed inslude function as composer already do that
[Bundle] Keep lazy loading of DIC
[Bundle] config: collector keys are not longer required, usefull for dev env
[Bundle] Removed Bundle::shutdown as it is never called
[Bundle] Do not clear registry on flush

Because flush can be triggered severals time from a cli task during the process
[Bundle] Cleaned extension
[Bundle] Fixed tests
[Bundle] Removed tests on kernel::shutdown
[Bundle] Added more tests