Renamed Jam\Runner to Jam\Bootstrapper

* Moved classes from Jam\Runner to Jam\Bootstrapper;
* Removed unused files;
* Refactoring on Jam\Bootstrapper\Bootstrap class
* Created class that loads and stores providers;
* Changed interface of providers;
* Refactoring on PHP provider;
* Refactoring on autoloaderPrefix provider;
* Created some examples.