Assertive-Chai Based Specs to test Bacon.js on IE8

Pull Request to demonstrate #426
=====

*Note*: IE8 is not supported by Expect API of `chai.js`. To work around this limitation, I used `assertive-chai` npm module that exposes only Assert API of `chai.js`.
* The *Assertive* version of specs can be found under `ie8` directory.
* The *Assertive* version was written using a helper module to convert Expect API to Assert API. I am unsure if I should've committed it. 

Please feel free to use as required.

To Run:
======

* `npm install && cd ie8 && ./browserify.sh` - This will generate new `bundle.js ` under `browsertest` directory,  using `Assertive*.coffee` spec files under `ie8` directory.
* Open IE8 browser and open page to `<Protocol>://<Host>[:<Port>]/ie8/mocha.runner.html`
* If the tests do not load, open the Debugger (F12)-> clear cache -> Start debugging -> Prompt for reload page -> Agree

To Simulate #426 
========
Replace line `forNow = schedule[currentTick].splice(0, schedule[currentTick].length)` in AssertiveTickScheduler.coffee with `forNow = schedule[currentTick].splice(0)`

IE8 will timeout.