Ignore directories created by JetBrains IDEs.

(cherry picked from commit c470de572c2f63e7ba5eeb7d97bc1f4bc114b375)
diff --git a/examples/.gitignore b/examples/.gitignore
index d56b94f..2b5671a 100644
--- a/examples/.gitignore
+++ b/examples/.gitignore
@@ -40,3 +40,7 @@
 
 ## Dear ImGui Ini files
 imgui.ini
+
+## JetBrains IDEs
+.idea
+cmake-build-*