Add unit tests about implements() and extends().
Add unit tests about implements() and extends().

CedCannes/atoum,jubianchi/atoum,tejerka/atoum,mageekguy/atoum,vonglasow/atoum,agallou/atoum,tejerka/atoum,jubianchi/atoum,mikaelrandy/atoum,mageekguy/atoum,vonglasow/atoum,agallou/atoum,Tiross/atoum,GuillaumeDievart/atoum,Tiross/atoum,CedCannes/atoum,gpaton/atoum,gpaton/atoum,GuillaumeDievart/atoum,mikaelrandy/atoum