Remove npm-shrinkwrap file (#42)

* Remove npm-shrinkwrap file

Including the `npm-shrinkwrap.json` file [causes an npm error][issue] for users
installing the `codeclimate-test-reporter` package on Node `4`.

Since shrinkwrap-ing doesn't provide much value in the context of a published
package, this commit simply removes the file.

[issue]: #41

* Disable nodesecurity engine from CC analysis

We removed the `npm-shrinkwrap.json` file so this engine is no longer
appropriate.

Author: dblandin

.codeclimate.yml

@@ -1,7 +1,5 @@
 ---
 engines:
-  nodesecurity:
-    enabled: true
   duplication:
     enabled: true
     config:
@@ -14,7 +12,6 @@ engines:
 ratings:
   paths:
   - "**.js"
-  - "npm-shrinkwrap.json"
 exclude_paths:
 - node_modules/**/*
 - test/**/*