Fix all the resting errors to have a valid swagger file.

They are still some warnings but nothing blocking.

Doing so I found that some request still misses son parameters for some POST/PUT/PATCH request. This means the a client generated from the swagger file will not work completely. 

Fix #4088 by activating validation in drone
Should fix #4010.

* API endpoint for testing webhook

* Empty commit to rerun CI

* Fix API status code for hook creation

* Named constants for response statuses

* Update swagger documentation

Add docs for missing endpoints
Add documentation for request parameters
Make parameter naming consistent
Fix response documentation

* Restore delete comments

* Add swagger comment for adminCreateOrg

* Add swagger comment for admin route

* add hook swagger doc

* Add tags

* Add auth

* Fix name of responses

* Edit name method

* Update vendor

* make generate-swagger

- Generate swagger.json into public/
- Add swagger-ui auto-installation
- Add footer link to local swagger-ui
- Add /swagger url for using app url.
- Fix Swagger-UI version via git tag

From code.gitea.io/go-sdk/gitea
  To code.gitea.io/sdk/gitea

- Update import paths from github.com/go-gitea to code.gitea.io
- Fix import path for travis

See https://docs.travis-ci.com/user/languages/go#Go-Import-Path

See https://github.com/golang/go/wiki/CodeReviewComments#mixed-caps

Allows the deletion of a webhook from a repository at the
/:user/:repo/hooks/:id endpoint.

Solves drone/drone issue #1603.

Signed-off-by: Dennis Chen <barracks510@gmail.com>

This prevents user retrieve arbitrary webhook by changing URL to
access webhook from other unauthorized repositories.

- Fix go-gogs-client#10
- Related to #809

- POST /user/repos
- POST /org/:org/repos