anchor.diff:  + Response 200
   
     [Access Token][]
  +
  +## Authorization Code [/oauth/authorize{?client_id,response_type,redirect_uri}]
  +
  +### Get an authorization code [GET]
  +
  +Client will be redirected to the authorization web page. After picking authorization method and
  +successfully authorizing she will be redirected back to the `redirect_url` with authorization
  +`code`. Authorization code should be exchanged to the access token using `token` endpoint.
  +
  ++ Parameters
  +    + client_id: web (string, required) - Client app identifier.
  +    + response_type: code (string, required) - Response type.
  +    + redirect_uri: https://tvarkaumiesta.lt/auth/callback (string, required) - Redirect uri.
  +
  ++ Response 302
   
   ## VIISP Access Token [/auth/viisp/new{?redirect_uri}]
   
  
positive.code: and pass it to the token endpoint via `assertion` attribute.
  
  + Attributes
      + client_id: android (string, required) - Client app identifier. One of: *android*, *ios*, *web*.
      + grant_type: password (string, required) - OAuth2 grant type. One of: *password*, *assertion*.
      + scope: user (string, optional) - Access scope.
      + username: gediminas@vilnius.lt (string, optional) - User's email address. **Required for password grant type**.
      + password: secret (string, optional) - User's password. **Required for password grant type**.
      + provider: google (string, optional) - Assertion provider. One of: *google*, *facebook*, *viisp*. **Required for assertion grant type**.
      + assertion: token123 (string, optional) - Google/Facebook/VIISP token. **Required for assertion grant type**.
  
  + Request Create a token using email/password.
  
              {
                  "client_id": "android",
                  "grant_type": "password",
                  "scope": "user",
                  "username": "gediminas@vilnius.lt",
                  "password": "secret"
              }
  
negative.code: 
  Pass `guest` value as username/password.
  
  #### Web authorization
  
  Grant type: `authorization_code`
  
  First get authorization using `authorize` endpoint and pass it via `code` attribute. Also pass
  `redirect_uri` which should be the same as passed to the `authorize` endpoint.
  
  #### Login with email and password
  
  Grant type: `password`
  