Changed getFutureMeeting by date method.
This now finds a meeting with the specified date, then calls 2 separate helper methods:
1. checks items down (earlier) in meetingList. If the dates match the search date, it adds them to the list to return.
2. checks items up (later) in meetingList and adds these if the date matches the search date.
These lists are then combined (ensuring they aren't empty) and returned.
Added test checking constructor of addNewPastMeeting
Added test checking correct exceptions thrown by addNewPastMeeting
Finished addNewPastMeeting method
Added tests to ensure correct meeting(s) returned for getPastMeeting.
I.e. when searching by contact
Amended getPastMeeting to return PastMeetings