TT#15750 Add our own npm registry cache to .npmrc

From now we have npmlazy cache available so let's use it wherever
possible. Exact dependencies versions must be controlled via
npm-shrinkwrap.json file otherwise we have no guarantee each time
package is build with the same dependencies tree.

Change-Id: Iac883b23d9d945857df9674020fc19df35bde453

.npmrc

@@ -0,0 +1 @@
+registry = https://npm-registry.sipwise.com/