Add new snowblock for "npm"

Created a new snowblock for NPM (1) including the ".npmrc" configuration
file (2) to define

* the "npm init" (3) options
  * init-author-name
  * init-author-email
  * init-author-url
  * init-version
  * init-license
* the "package-lock" option with "false" to disable the generation of
  the "package-lock.json" (4) file
* the "save-exact" option to always save the exact dependency versions
  in the "package.json" (5)

References:
  (1) https://www.npmjs.com
  (2) https://docs.npmjs.com/files/npmrc
  (3) https://docs.npmjs.com/misc/config
  (4) https://docs.npmjs.com/files/package-lock.json
  (5) https://docs.npmjs.com/files/package.json

GH-95

snowblocks/npm/npmrc

@@ -0,0 +1,14 @@
+; Copyright (c) 2016-2017 Arctic Ice Studio <development@arcticicestudio.com>
+; Copyright (c) 2016-2017 Sven Greb <code@svengreb.de>
+
+; Project:    igloo
+; Repository: https://github.com/arcticicestudio/igloo
+; License:    MIT
+
+init-author-name=Arctic Ice Studio
+init-author-email=development@arcticicestudio
+init-author-url=http://arcticicestudio.com
+init-version=0.0.0
+init-license=MIT
+package-lock=false
+save-exact=true

snowblocks/npm/snowblock.json

@@ -0,0 +1,15 @@
+[
+  {
+    "clean": ["~"]
+  },
+  {
+    "link": {
+      "~/.npmrc": {
+        "hosts": {
+          "archbook": "npmrc",
+          "igloo": "npmrc"
+        }
+      }
+    }
+  }
+]