Adding Haskell examples (#17)

* Adding binary search example for Haskell

* Adding selection sort example in Haskell

* Adding Haskell examples for chapter 3

* Adding examples for chapter 4

* Adding examples for chapter 5

* Adding git ignore

* Add Haskell example for BFS

03_recursion/Haskell/02_greet.hs

@@ -0,0 +1,12 @@
+
+greet2 name = putStrLn ("how are you, " ++ name ++ "?")
+
+bye = putStrLn "ok bye!"
+
+greet name = do
+  putStrLn ("hello " ++ name)
+  greet2 name
+  putStrLn "getting ready to say bye..."
+  bye
+
+main = greet "adit"