Unit tests: add vows (#57)

* add dependency
* add test runner entry in package.json
Add a simple unit test for public API
travis: fetch all dependencies
Test events handling
Complete phantomas API unit test
Mock for testing modules
Complete unit test for requestsMonitor module

* separate instance of phantomas mock for each topic
Linting
Add a unit test for domains module
Add mock.getContext() helper
domains: simplify unit test
Merge pull request #57 from macbre/unit-tests-foundation

Prepare a foundation for writing unit tests for phantomas modules