Added a Post.Del method.
Merge pull request #46 from lieuwex/master

Added a Post.Del method.
Fix several problems with ListingEnumerator

I was totally overthinking this when I first wrote it. Works fine now.

Closes #48 and closes #34
Correctly handle the end of a listing
Merge branch 'master' of https://github.com/SirCmpwn/RedditSharp
Upped version