Ignore MacOS DS Store

Change-Id: I2396004d839bc7465e56493a9edee0d1256c8cf3
diff --git a/.gitignore b/.gitignore
index 52cb35b..4f16b0f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,6 @@
 # Scala-IDE specific
 .scala_dependencies
 .worksheet
+
+# macOS
+*.DS_Store