Problem 51: Fix 'wildcards :: String -> [String]' to not throw out Strings which begin with one or more '*' characters and then only contain digits
Problem 61: Move partial solution from old/problem61.hs to problem061.hs
Tweak formatting
Problem 61: Implement 'discriminant :: Integer -> Integer -> Integer -> Integer'
Problem 61: Implement 'isQuadraticSolutionInteger :: Integer -> Integer -> Integer -> Bool'
Problem 61: Modify main to zip list of numbers with results of isTriangle
Problem 61: Implement 'isPentagonal :: Integer -> Bool'
Problem 61: Implement 'isHexagonal :: Integer -> Bool', 'isHeptagonal :: Integer -> Bool', 'isOctagonal :: Integer -> Bool'; fix bug in `isQuadraticSolutionInteger :: Integer -> Integer -> Integer -> Bool'
Problem 61: Fix type errors in 'isQuadraticSolutionInteger :: Integer -> Integer -> Integer -> Bool'