Group support

[briehl]

This is a pretty massive change.

All "entities" (actors, objects, targets and users) are specifically designated as such by a structure. So, this goes from defining a notification as

{
    "actor": "some_user",
    "verb": "shared",
    "object": "123",
    "target": ["another_user"]
}

to this, which is more verbose but easier to parse for the UI, other services, and the feeds service itself:

{
    "actor": {
        "id": "some_user",
        "type": "user"
    },
    "verb": "shared",
    "object": {
        "id": "123",
        "type": "narrative"
    },
    "target": [{
        "id": "another_user",
        "type": "user"
    }]
}

That's about the crux of the change. This is just BIG, because it affects just about every code module in the repo.

[briehl]

This also includes stubs and support for the Groups, Workspace, Narrative, and Jobs services. Not so much jobs, but there's some code stubs there.

[coveralls]

Pull Request Test Coverage Report for Build 172

• 421 of 482 (87.34%) changed or added relevant lines in 28 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-1.8%) to 89.914%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
feeds/api/util.py	14	16	87.5%
feeds/entity/types/user.py	22	24	91.67%
feeds/external_api/jobs.py	2	4	50.0%
feeds/managers/fanout_modules/kbase.py	1	3	33.33%
feeds/entity/types/admin.py	13	16	81.25%
feeds/external_api/groups.py	22	25	88.0%
feeds/actor.py	7	11	63.64%
feeds/entity/types/group.py	14	21	66.67%
feeds/entity/types/job.py	14	23	60.87%
feeds/external_api/workspace.py	54	81	66.67%

Totals
Change from base Build 167:	-1.8%
Covered Lines:	1364
Relevant Lines:	1517

---

💛 - Coveralls

[briehl]

Trying this again.
Now, the code in entity.py that split apart based on the entity type (for doing id and name lookup) is now branched out into different modules. As it should've been.