1.   Added Tracy exception handler in core. Handle exception and log it.

2.   Dynamic finder method findBySql() altered to fetch all records from database. Return PDO object.
3.   Added container class into the core.
4.   Dependency Injection- Controller injection with type hinting and property, interface injection or act as service.
5.   if (!class_exists($controller)) {
    throw new Exception('Unhandled Exception (404 Page)');
    }
    Added into Dispatcher class to handler 404 page
6.  Remove unwanted code and Improved coding and doc.