Swagger (#124)

* start experimenting with swagger documentation

* further adventures in swagger

* do a few more api paths

* account paths documented

* go fmt

* fix up some models

* bit o lintin'

docs/api/swagger.md

@@ -0,0 +1,9 @@
+# API Documentation
+
+GoToSocial uses [go-swagger](https://github.com/go-swagger/go-swagger) to generate a V2 [OpenAPI specification](https://swagger.io/specification/v2/) document from code annotations.
+
+The resulting API documentation is rendered below, for quick reference.
+
+If you'd like to do more with the spec, you can also view the [swagger.yaml](/api/swagger/swagger.yaml) directly, and then paste it into something like the [Swagger Editor](https://editor.swagger.io/) in order to autogenerate GoToSocial API clients in different languages, convert the doc to JSON or OpenAPI v3 specification, etc. See [here](https://swagger.io/tools/open-source/getting-started/) for more.
+
+!!swagger swagger.yaml!!

docs/swagger.go

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+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+// Package docs GoToSocial
+//
+// GoToSocial Swagger documentation.
+//
+//     Schemes: https, http
+//     BasePath: /
+//     Version: REPLACE_ME
+//     Host: example.org
+//     License: AGPL3 https://www.gnu.org/licenses/agpl-3.0.en.html
+//     Contact: GoToSocial Authors <admin@gotosocial.org>
+//     SecurityDefinitions:
+//       OAuth2 Bearer:
+//         type: oauth2
+//         flow: accessCode
+//         authorizationUrl: https://example.org/oauth/authorize
+//         tokenUrl: https://example.org/oauth/token
+//         scopes:
+//           read: grants read access to everything
+//           read:accounts: grants read access to accounts
+//           write: grants write access to everything
+//           write:accounts: grants write access to accounts
+//           write:blocks: grants write access to blocks
+//           write:follows: grants write access to follows
+//           admin: grants admin access to everything
+//           admin:accounts: grants admin access to accounts
+//       OAuth2 Application:
+//         type: oauth2
+//         flow: application
+//         tokenUrl: https://example.org/oauth/token
+//         scopes:
+//           write:accounts: grants write access to accounts
+//
+// swagger:meta
+package docs