Update lib/statsd.js

There are quite a few changes here.  

* Ensured there were no more global memory leaks
* Added defaults to the initializer variables. The default host is `localhost` and the default port is `8125`
* Added Prefix and suffix to class to allow users to specify what the name of each stat will start and end with.  This allows for things like `<environment>.<project>.<stat>.<machine-name>` and other templates.
* Added a globalize function that gives the user the option to make this instance of statsd global
* Standardized all functions to take a `stat`, `value`, `sampleRate` (optional), and `callback` (optional)
* Added an optional `callback` to each of the functions that will get called when the message is successfully sent
* Standardized on camel case in accordance with the JS recommended styl guide
* Added a default value of `1` for increments and `-1` for decrements
* Added an alias of `unique` to `set` as set is rather ambiguous
* Removed `mersenne` dependency as V8s `Math.random()` is faster and still provides an even distribution. For sampling purposes this is sufficient, we don't need cryptographic security or seeds here.
* Added full JSDoc style comments to all methods.
package.json updates
  * Upped the version to 0.4
  * Added myself as a contributor :)
  * Removed OS dependencies as we should not prevent someone from installing the package unless we know for a fact it doesn't work on that OS
  * Removed mersenne dependencies
  * Changed main to be index.js as this is the accepted standard
moved the requires to the top to prevent from hitting the requires cache every time the client is initialized
added index.js as the root of the project
added unit tests to ensure that future code updates to do break existing functionality
updated travis.yml to run the tests
travis fail
remove superfluos space
Made test running compatible with Windows

"npm test" wouldn't run under Windows due to the fact that Windows
doesn't support shebang style executable scripts. Also the default
binding for UDP Datagram servers is 0.0.0.0 which is invalid for
Windows. I specified the binding in the test to be 127.0.0.1 and now
everything passes and runs properly.
added ability to pass an array as the stat.  StatsD will send a message for each item in the array with the same value
fixed an issue where it calls back more than once on arrays, added tests to prevent regression
Merge pull request #26 from devdazed/master

Refactored and added a few useful features.