add acceptance test framework based on node jasmine

This is an experiment on solving #1 using node jasmine

**Prerequisites**:
1. Installed node

**How to run**:
1. Run `npm install` to install a local copy of `jasmine-node` and run tests (which are set up as a post-install script)
2. Consecutive tests can be run with `npm test`

Tests are located in `spec` directory. Each filename must end with `.spec.js`

Pros:
+ only one prerequisite 
+ simple directory structure and minimal setup needed

Cons:
+ supports only BDD test style out of the box