Add documentation comments for the first group of methods

I wrote up a few appledoc style documentation comments for the first set of methods. I find these to be useful when using the in context documentation browser in Xcode, which appears when alt clicking on a method. In particular, I like being able to see the object type of an input parameter (similar to how methods in Apple libraries appear in the documentation browser), or what type of object an array contains, without having to open the library in a new tab or the assistant editor. It helps me to stay in the flow while programming.