Added resource embedding. Allows a query string ?embedded={"user": 1} to request embedded serialized resource representations. Resources must have a defined `data_relation` with `embeddable = True`.
Embedded documents: added unit test, got it to pass
Python3 fix: simplejson instead of built-in json
Added `find_list_of_ids` to io.mongo to support embedding lists
of resources.
version(changed|updated) align to current release.
Docs for Embedded Resource Serialization.
Merge branch 'bcattle-resource_embedding' into develop

Conflicts:
	docs/config.rst
	eve/default_settings.py
	eve/flaskapp.py
	eve/methods/get.py
	eve/tests/methods/get.py

Closes #68.
Embedded Resources Serialization: limitations.
Changelog updated: Embedded Resources Serialization.