Works on my end

Only touched these files
Merge pull request #77 from ylevitsk/master

error checking, new jar
Merge pull request #78 from HexSoftware/Databaseworkalready

Works on my end
testcategory and testcategoryNum

and typo fix
implemented editing questions
Merge pull request #79 from RAlmada/master

implemented editing questions
Display tests from testdb. student
Merge pull request #80 from lambchopz/master

Display tests from testdb. student
added grader