Move Interfaces to Framework. Next step to major refactoring.
Move concrete classes to base directory.
Fix references after moving.
Move Example Test and Group Test to match refactoring.
Update references.
* Move class reference to constant and use throughout.
* Update reference.
Update factory names for creating new group and example.
Remove constructor and add initialize method.
Add with helper function and update references.
Add initialize method to interface with inline documentation.
Remove constructor.
Update functions to work with changes to factory and group interface.
Fix factory tests.
Add group to world.
GroupInterface and CallSiteInterface extends CommonInterface.
Update references and add inline documentation to helper static method.
Update inline documentation for describe and context.
Match interface changes.
* Improve inline documentation.
* New helper method to reduce duplication.
Fix example tests.