Binders / Collections / Books

__Note:__ I used the pickle storage for this PR.  I'm hoping that @reedstrm will add something to the postgresql storage to get this to work.  But this can be used in development.

Creating a new page:

`wget -q -O - --post-data='{"title": "Page one"}' http://localhost:8080/contents`

```
{
    "license": {
        "url": "http://creativecommons.org/licenses/by/4.0/",
        "version": "4.0",
        "name": "Attribution",
        "abbr": "by"
        },
    "language": "en",
    "created": "2014-03-25T14:28:47.914416+01:00",
    "derivedFrom": null,
    "abstract": null,
    "title": "Page one",
    "modified": "2014-03-25T14:28:47.914578+01:00",
    "mediaType": "application/vnd.org.cnx.module",
    "content": null,
    "version": "draft",
    "submitter": "me",
    "id": "1b194013-a03b-4707-8e8e-5fe33a3278fc"
    }
```

Creating a new book with the page:

`wget -q -O - --post-data='{"title": "Book", "mediaType": "application/vnd.org.cnx.collection", "tree": {"contents": [{"id": "1b194013-a03b-4707-8e8e-5fe33a3278fc@draft", "title": "Page one"}]}}' http://raring:8080/contents`

```
{
    "license": {
        "url": "http://creativecommons.org/licenses/by/4.0/",
        "version": "4.0",
        "name": "Attribution",
        "abbr": "by"
        },
    "language": "en",
    "created": "2014-03-25T14:29:59.701826+01:00",
    "derivedFrom": null,
    "abstract": null,
    "title": "Book",
    "tree": {
        "id": "56a6c08e-af0f-4535-a2ac-e356eba7c54a@draft",
        "contents": [
            {
                "id": "1b194013-a03b-4707-8e8e-5fe33a3278fc@draft",
                "title": "Page one"
                }
            ],
        "title": "Book"
        },
    "modified": "2014-03-25T14:29:59.702055+01:00",
    "mediaType": "application/vnd.org.cnx.collection",
    "content": null,
    "version": "draft",
    "submitter": "me",
    "id": "56a6c08e-af0f-4535-a2ac-e356eba7c54a"
    }
```

Deriving a book from archive:

`wget -q -O - --post-data='{"derivedFrom": "feda4909-5bbd-431e-a017-049aff54416d@1.1"}' http://raring:8080/contents`

```
{
    "license": {
        "url": "http://creativecommons.org/licenses/by/4.0/",
        "version": "4.0",
        "name": "Attribution",
        "abbr": "by"
        },
    "language": "da",
    "created": "2014-03-25T14:41:35.654800+01:00",
    "derivedFrom": "feda4909-5bbd-431e-a017-049aff54416d@1.1",
    "abstract": null,
    "title": "Copy of Madlavning",
    "tree": {
        "id": "fb372a0f-ad70-49a1-a026-1e46685ae11c@draft",
        "contents": [
            {
                "id": "91cb5f28-2b8a-4324-9373-dac1d617bc24@1",
                "title": "Indk\u00f8b"
                },
            {
                "id": "f6b979cb-8904-4265-bf2d-f059cc362217@1",
                "title": "F\u00f8devarer"
                },
            {
                "id": "7d089006-5a95-4e24-8e04-8168b5c41aa3@1",
                "title": "Hygiejne"
                },
            {
                "id": "b0db72d9-fac3-4b43-9926-7e6e801663fb@1",
                "title": "Tilberedning"
                }
            ],
        "title": "Copy of Madlavning"
        },
    "modified": "2014-03-25T14:41:35.654960+01:00",
    "mediaType": "application/vnd.org.cnx.collection",
    "content": null,
    "version": "draft",
    "submitter": "me",
    "id": "fb372a0f-ad70-49a1-a026-1e46685ae11c"
    }
```