Post routes

[SoftlySplinter]

The Generic, Status, Essay and Repost types are complete, but the rest of the types need doing (which should be easy).

https://tent.io/docs/post-types

[borntyping]

The models for this are currently being worked on as part of issue #16.

[borntyping]

We now have models for the the Status, Essay and Repost types, so it's just the frontend API end of the posts needed now.

[SoftlySplinter]

That's the server-side data complete. Now there's also some client-used routes which need to be set up:

• New posts via POST /posts
• The GET /posts request needs to check for authorisation to be able to return all or just the public ones. Same for GET /posts/<id>
• Attachments via POST /posts, getting via GET /posts/<post_id>/attachments/<name>
• Mentionds via GET /posts/<id>/mentions
• Updates via PUT /posts/<id>
• Versioning via GET /posts/<id>/versions
• Deletion via DELETE /posts/<id>
• Specific version deletion via DELETE /posts/<id>?version=<version_id>

[borntyping]

#51 means there is now just a single Post type, so completing multiple post types isn't an issue.

[SoftlySplinter]

I think I'm going to halt this for now. Whilst it would be nice to have versioning, mentions and attachments, I'd rather have something simple working :)

[SoftlySplinter]

Raised issues #52, #53 and #54 to track versioning, mentions and attachments. The authorisation should probably tie into #22.