Annotate the package to ensure it is installed only via gopkg.in/poker.v0

Feature introduced in Go 1.4

https://docs.google.com/document/d/1jVFkZTcYbNLaTxXD9OcGfn7vYv5hWtPx9--lTx1gPMs/edit
Iterate over the ranks and suits to create the deck.
Implement the API, the way I think it should be, 100% coverage is coming
Unit test the new API
Re-write shuffle to be more efficient. NewDeck always calls shuffle()
Re-write the rand indexer to be completely random by using a rand seed
Document all of the packages.
Merge pull request #2 from go-poker/v0.rewrite_the_api_and_document

Rewrite the api and document