add Sinon.JS support for mocha

sinon.js is built from https://github.com/javenwang/Sinon.JS/tree/ti-sinon
I modify sinon to make it suitable for titanium environment

You should upgrade your tishadow app before you can use Sinon.JS
```
tishadow app -u -d <your tishadow app path>
```
Merge pull request #267 from javenwang/sinon

add Sinon.JS support for mocha