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[ncw]

I've been using your library to add an Amazon Cloud Drive backend to rclone (see http://rclone.org )

I've managed to make the test suite pass with it. In the process I've added quite a few things to your library. I've tried not to break the external API in the process.

Here is the jumbo commit for you to look at. With a bit of effort I could break this up into smaller commits if you want.

* AccountService methods
  * GetEndpoints - gets the users endpoints.
    * Updates the endpoints in the client when called
    * The library doesn't work in Europe unless you call this first
* Node methods
  * Add more fields to Node struct
  * Trash
  * Add NodeFromId for clients who wish to manage their own IDs
* File methods
  * Open - returns an io.ReadCloser to download a file
  * Make GetNode, GetFolder, GetFile return ErrorNotFound if appropriate
  * Overwrite - ovewrites an existing file from an io.Reader
* Folder methods
  * CreateFolder
  * Put - uploads a file from an io.Reader
  * FolderFromId for clients who wish to manage their own IDs
* Fixes
  * Fix error reporting so that it does return the Amazon error in the body
  * Fix escaping of names in query with EscapeForFilter
* Internal
  * Changed Client.Do so that it can return an unclosed resp.Body

[ncw]

@sgeb any thoughts on the above? I have the acd support completely working in rclone now, and I have a few more patches I could add if you are interested.

Thanks

Nick