Add pipe and pin operators koans

lib/koans/05_functions.ex

@@ -92,4 +92,13 @@ defmodule Functions do
   koan "You can 'capture' functions if you want to pass them around as values" do
     assert multiply_then_call(2, &square/1) == 100
   end
+
+  koan "functions can be combined elegantly with the pipe operator" do
+    result = "full-name"
+    |> String.split("-")
+    |> Enum.map(&(String.capitalize(&1)))
+    |> Enum.join(" ")
+
+    assert result == "Full Name"
+  end
 end

lib/koans/09_pattern_matching.ex

@@ -5,6 +5,16 @@ defmodule PatternMatching do
     assert match?(1, 1)
   end
 
+  koan "a pattern can change" do
+    a = 1
+    assert a = 2
+  end
+
+  koan "a pattern can also be strict" do
+    a = 1
+    assert ^a = 2
+  end
+
   koan "patterns can be used to pull things apart" do
     [head | tail] = [1,2,3,4]