Add examples on Swift 3.0.2 (#11)

* 01_binary_search Swift 3.0.2

* 01_binary_search Swift 3.0.2

* add Chapter 2 - 01_selection_sort Swift 3.0.2 example

* 01_binary_search cosmetic note updates Swift 3.0.2

* 03_recursion Swift 3.0.2 examples

* 04_quicksort Swift 3.0.2 examples

* fix typo on quicksort example. Swift 3.0.2

* add  05_hash_tables examples on Swift 3.0.2

* add 01_breadth-first_search Swift 3.0.2 example

* 01_breadth-first_search fixing typo Swift 3.0.2

* add 01_dijkstras_algorithm on Swift 3.0.2

* add 08_greedy_algorithms Swift 3.0.2 example

* 01_longest_common_subsequence Swift 3.0.2 example

03_recursion/swift/01_countdown.swift

@@ -0,0 +1,16 @@
+import Foundation
+
+func countDown(i : Int) {
+    print(i)
+    // base case
+    if i <= 0 {
+        return
+    } else {
+        // recursive case
+        countDown(i: i-1)
+    }
+}
+
+countDown(i: 5)
+
+

03_recursion/swift/02_greet.swift

@@ -0,0 +1,18 @@
+import Foundation
+
+func greet2(name: String) {
+    print("how are you, \(name) ?")
+}
+
+func bye() {
+    print("ok bye!")
+}
+
+func greet(name: String ) {
+    print("hello, \(name)!")
+    greet2(name: name)
+    print("getting ready to say bye...")
+    bye()
+}
+
+greet(name: "adit")

03_recursion/swift/03_factorial.swift

@@ -0,0 +1,12 @@
+import Foundation
+
+func fact(x: Int) -> Int {
+    if x == 1 {
+        return 1
+    } else {
+        return x*fact(x: x-1)
+    }
+}
+
+
+print(fact(x: 5)) // => 120