Added Tests and Refactored (EECE 310 L2A1 - revised)

This pull request is almost the same as Issue #194, but with the requested changes implemented.

Changes include:
* Addition of an @After method to stop the server in WebServerTest
* Cleanup of SampleCrawlersTest
* Application of hamcrest in UrlUtilsTest, DOMComparerTest, WebServerTest
* Removal of unnecessary inline declarations in HtmlNameSpaceTest
* Removal of final in methods of DomUtilsTest

@rsingla92 @jordenh @lordy1992