Align category API with other APIs

[teemukataja]

Is your feature request related to a problem? Please describe.
The different APIs follow a distinct pattern POST /api/{item}/create:

POST /api/applications/create
POST /api/licenses/create
POST /api/forms/create
POST /api/resources/create
POST /api/catalogue-items/create

We are programmatically creating items using the pattern /api/{item}/create and would like to be able to use the same pattern with categories as well, but at the moment its API is slightly different from the others.

Describe the solution you'd like
Update categories API to follow the same convention as other APIs.

POST /api/categories/create

instead of

POST /api/categories

The following is not important to us, but the same can be seen in updating items:

PUT /api/categories

vs

PUT /api/{items}/edit

Additional context
GET already works the same for all items. 👍

GET /api/{item}
GET /api/{item}/{item-id}

[Macroz]

Looks good. A consistent API is desireable.

The categories API is perhaps more consistent with typical REST practices, but our CQRS style with commands is perhaps the one we should follow (with /create and /edit). We can add these and keep the old ones for backwards compatibility for now.

[aatkin]

We could also change organizations API PUT /edit into POST /edit for consistency.

[Macroz]

Actually, it seems we have all the edits as PUT so the org should remain. But I noticed PUT /api/user-settings needs the /edit too.

[Macroz]

@teemukataja This is now merged to master, if you want to test it already. It should appear in the next release in a while.