Wrote first test for the path of dustjs

Will be using NPM CLI to check the installation path of the
dustjs-linkedin package in order to grab the core.js file based on user
installation.
Using NPM CLI to get realPath of dustjs-linkedin

Dealing with callbacks, so wrote this separately to find out what can be
pulled from the command and how it looks.
Moved mocha options to mocha.opts file

Setting all command line flags from `npm test` mocha command in
`mocha.opts`. Now using nyan reporter bc d'aaaaawwww.
Dustcore js file is now dynamically found.

Added two test cases to check if dustcore file path is correct - check
if it contains the core node_modules path and the version number.
Getting the path to the module via `require` and the version number via
the `package.json` file for `dustjs-linkedin`.
Merge pull request #3 from mgarbacz/smart-dust-path

Smart dust path