Completed the BreadthFirstAgenda class. It can now be used as an Agenda
to solve problems. 

Completed the framework, can now have any action state pairs plugged
into it.

Changed some other method minorly in order to be able to better find get
a solution to some problems!
Merge pull request #2 from DaveM214/master

Completed the BreadthFirstAgenda class. It can now be used as an Agenda