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

01_introduction_to_algorithms/swift/01_binary_search.swift

@@ -0,0 +1,31 @@
+import Foundation
+
+// Note: If you aren’t familiar with Comparable, please check out “Generics” chapter in Swift book
+func binarySearch <T: Comparable>(_ list: [T], item: T) -> Int? {
+    // low and high keep track of which part of the list you'll search in.
+    var low = 0
+    var high = list.count - 1
+    // While you haven't narrowed it down to one element ...
+    while low <= high {
+        //... check the middle element
+        let mid = low + (high - low) / 2
+        let guess = list[mid]
+        // Found the item.
+        if guess == item {
+            return mid
+        }
+        // The guess was too high.
+        if guess > item {
+            high = mid - 1
+        } else {
+            low = mid + 1
+        }
+    }
+    
+    return nil
+}
+
+let myList = [1, 3, 5, 7, 9]
+print(binarySearch(myList, item: 3) ?? "Not Found") // => 1
+print(binarySearch(myList, item: -1) ?? "Not Found") // => Not Found
+