-----------------------------Class UI Changes-----------------------------
- attached crawl button to WebCrawler class
- prints all websites crawled when user clicks 'crawl' button

-----------------------------Class WebCrawler Changes-----------------------------
Added 3 accessor methods:

- getURLs (returns the queue of urls to be parsed, used for testing purposes)
- getKeyWords (returns the search keywords, used for testing purposes)
- getWebSitesCrawled (returns all the websites crawled when user clicks the 'crawl' button)