GPII-564: Individual acceptance tests for NVDA and built-in windows features

* Split acceptanceTests.js into three files: 
** AcceptanceTests_include.js - containing functions and includes used across the acceptance tests
** AcceptanceTests_nvda.js - containing the acceptance tests for NVDA
** AcceptanceTests_builtIn.js - containing the acceptance tests for the built in features of windows
* Created two config files (one of NVDA, one for built in), ensuring that the device reporter uses the correct device reporter file

This pull request should be reviewed with https://github.com/GPII/universal/pull/212

Documentation: http://wiki.gpii.net/index.php/Writing_Acceptance_Tests