Basic operators now works with Jsoup library

Still have to implement and test the advanced functions like embed,
etc...
Add some tests

Add The Junit Library to the project
Remove the useless testdata package
Implement some tests on the basic operators, the test queries are under
the test_queries folder and should be written above each test.
Add tests for link function and add link function for Jsoup
Merge branch 'thomas'
Merge branch 'goto'
Change tables into div for HTML and switched to the flexbox layout fro Jsoup. Also finish implementing a first version of the function for Jsoup and added some styles