Small change to MathProblem, changed the isLeaf function so if either of the arguments are not a MathProblem it is qualified as a leaf
Changed the semantics of the isLeaf function, added two methods to check each of the arguments for numbers
Added a solve method to TaskAdmin which will recursivly solve a MathProblem by auctioning problems. Changed the name of two methods in MathProblem
Auction is now mostly done, it doesn't use any fancy behaviors as the assignement demands, which may mean it need to be changed later