[Mono-osx] MonoMac: patch to add NSFileManager NSUrlDownload

[Miguel de Icaza]

Hello,

> *  adds NSUrlDownload and NSUrlDownloadDelegate
> *  adds bindings for NSFileManager and
> NSFileManagerFileOperationAdditions and NSDirectoryEnumerator

I did a bunch of changes, please review them when you get a chance


> *  NSFileManagerFileOperationAdditions, method names need to be
> changed.

This was actually the delegate, please try the resulting code.

> *  how should "unsigned long long" be bound? 

ulong