Updated features list.
Quickstart has precedence over Features.
Defaults that could be assimilated to None were ignored.

Reported by Yari Podio Casares:

We've found a problem when using default values in schema definitions; in
particular, when the default value can be assimilated with 'None' (0, False,
'').

If you try this schema:

test = {
    'schema' : {
        'name': {
            'type' : 'string',
            'required' : True,
            'default' : '',
        },
        'number': {
            'type' : 'integer',
            'required' : True,
            'default' : 0,
        },
        'yesno': {
            'type' : 'boolean',
            'required' : True,
            'default' : False,
        },
    },
}

...you can see that the three fields act as if the hadn't a 'default' value
defined (you cannot do a POST without speciffying a value for each field).
Merge branch 'develop' into simpler-edits
Properly serializing ObjectId fields.

Data drivers now expose a 'serializers' dictionary. This is then used by the
new eve.methods.common.serialize method to properly serialize certain field
types according to specific database needs.

ObjectId fields different from ID_FIELD are now properly serialized on
POST/PATCH/PUT methods, and can be filtered accordingly.

Limitations: eventual objectid and datetime values in nested documents are not
being serialized yet.

Closes #142. Partially addresses #136 (WIP).
Refactor try..except out of serialize().
Serialize both ObjectId and datetime values.

Serialize ObjectId and datetime values even in embedded lists and dictionaries.
Queries on nested ObjectId and datetime values.
Merge branch 'develop' into simpler-edits

Conflicts:
	CHANGES
	eve/tests/methods/patch.py
	eve/tests/methods/post.py
New tests updated to match new payloads.

Also, superfluous test removed.