Update
Fix pdf creation, an hrule without empty lines apparently tripped up pandoc.
Merge pull request #34 from kaylalewis/patch-1

Update
Kayla's revisions to Ch. 2 that were not merged.
Merge pull request #45 from kaylalewis/master

Kayla's revisions to Ch. 2 that were not merged.
html generated from github-markdown-preview

should not be retained
separated out what will actually go into ofBook, and kept the rest in back files
removed chapter numbering
Update chapter.md
chapter update
Update chapter.md
update
Delete .swp
Edited animation chapter
added a list of case study examples
writing intro to obj-c
talked about init and dealloc methods.
wrote about obj-c properties.
wrote about ARC
wrote about mixing obj-c and c++