Better support for Browserify and Webpack

Recently (actually last week), we released a new version of rollbar.js that has a few fixes to play
nicely with Browserify and Webpack. It's being served from our CDN and the source is on
GitHub.

We've also put together examples showing how to use rollbar.js with each. If you use Browserify or
Webpack and want to include rollbar.js that way instead of using our standard snippet, this is your
lucky day:

• Browserify example
• Webpack example

Thanks to @altano for helping with this.