More Lab 2 improvements from office hours

[50Wliu]

• fc89890 - Don't bother declaring ListItr as a friend of List
  • The justification for this is incorrect, as ListItr can't access List in the first place (only ListNodes).
  • https://piazza.com/class/k5bqcfbzltk49c?cid=121
  • https://piazza.com/class/k5bqcfbzltk49c?cid=71
• bab5bea - Hint more heavily to think about how many pointers need updating in the insert methods
  • This was, along with printList, the source of the most office hours help requests. I'm not sure I want to give away that it's four pointers though, hence the extra hint to think through it.
• a23f8b8 - Nudge students towards using public methods for printList
  • So. many. people. don't understand that printList is non-member and thus can't access private variables, and then they sit there stumped.

Overall, office hours went really smoothly this semester. We had a queue of 25 people for most of it, even though we were down a TA for an hour and half from 8 - 9:30! Most questions were some form of "I don't know how to printList if I can't use private variables" or "my printList isn't working" (problem with insertAtTail).

[aaronbloomfield]

The "friend class ListItr" has to stay in the List class, though...

[aaronbloomfield]

Wait! No it doesn't. I'm mixing up my classes here. Ignore my previous comment. Way too early to be merging pull requests, apparently...