did the constructor and the find
Added the second get function, and added throw messages for i<0 or i>items
it is kinda hard to keep forward and backward pointers straight sometimes.
Added and changed a number of things that would normally be done in multiple changes but I forgot.
Again, pointers are annoying, all works now, main.cpp now pauses, added some todo chanegs
Added answers to readme and made find work in more constant time
Merge pull request #20 from aczirkle/master

Final submit