Turn off npm default auditing

We have decide to avoid showing users of the prototype kit audit messages.

This is because a lot of the low level issues are not easy to fix, and will cause unnecessary worry.

We will prioritise the security alerts we recieve from GitHub's monitoring.

See #699 for the full discussion.

.npmrc

@@ -1 +1,2 @@
 package-lock=false
+audit=false