[Update] Array (from "Arrays and Dictionaries").

We can not always use the proposed version of the array initialization.
Swift can not initialize the array of items that have a generic type.
var emptyArray = T.GeneratorType.Element[]()   // error
var emptyArray: T.GeneratorType.Element[] = [] // success
[Update] Variable names and comments for arrays.
Merge pull request #26 from ruslanskorb/gh-pages

[Update] Array (from "Arrays and Dictionaries").