need to write a method that compares sets under ValuesManager, ie: a
contains b. Left a TODO <Current> tag where i left the previous work. 
Am having trouble in addNewPastMeeting  where checking the set of all
stored contacts for the input contacts is allways throwing an exception.
hence the need for the method above mentioned. Have overriden .equals
under contacts, so that should be enough for comparison. 
Next Steps:
test .equals() under Contacts
write test for <T>setContainsSet() under ValuesManager
pass the test
go back to <Current>TODO task