Merge pull request #1732 from jucrouzet/patch-1

Add .npm cache directory

Node.gitignore

@@ -26,3 +26,6 @@ build/Release
 # Dependency directory
 # https://docs.npmjs.com/misc/faq#should-i-check-my-node-modules-folder-into-git
 node_modules
+
+# Optional npm cache directory
+.npm