Add tasks for all the new languages

Task/Character-codes/Swift/character-codes-1.swift

@@ -0,0 +1,4 @@
+let c1: UnicodeScalar = "a"
+println(c1.value) // prints "97"
+let c2: UnicodeScalar = "π"
+println(c2.value) // prints "960"

Task/Character-codes/Swift/character-codes-2.swift

@@ -0,0 +1,8 @@
+let s1 = "a"
+for c in s1.unicodeScalars {
+  println(c.value) // prints "97"
+}
+let s2 = "π"
+for c in s2.unicodeScalars {
+  println(c.value) // prints "960"
+}

Task/Character-codes/Swift/character-codes-3.swift

@@ -0,0 +1,4 @@
+let i1: UInt32 = 97
+println(UnicodeScalar(i1)) // prints "a"
+let i2: UInt32 = 960
+println(UnicodeScalar(i2)) // prints "π"