Ignore IntelliJ IDEA project files

Change-Id: Idf9133e33871851b4e5b26fa3280f778153b9a79
diff --git a/.gitignore b/.gitignore
index d163d47..337f707 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,5 @@
 .project
 .classpath
 .settings
+.idea
+*.iml