Payload as a dict regardless of request content type.
PATCH: item-id wrapper removed from payloads.
PATCH tests updated for simplified payloads.

Some tests outside of TestPatch are still failing since I updated
tests.__init__.py. WIP.
Merge branch 'develop' into simplify
PUT: item-id wrapper removed from payloads.
PUT tests updated for simplified payloads.
POST: item-id wrapper removed from payloads.
POST: tests updated to reflect simplified payloads.
Test suite updated to reflect simplified payloads.
Docs update for 'no item-id payloads'
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).
Fix CORS for additional_lookup urls.

Currently OPTIONS are not handled within the app
so there are no CORS related headers in the response.
typo mistake authentication
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.
Updated arguments list for base auth classes.