Added .DS_Store to .gitignore

Change-Id: Ic59c5c1d12da084dcd07f5d8871cc09f9d6fa811
diff --git a/.gitignore b/.gitignore
index 1b6ba26..2905546 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,4 @@
 doc_venv
 _build
+
+.DS_Store