Add endpoint to get active sessions for user

[martynaslawinska]

Add API /session/active to get active sessions for user. Active sessions are returned for user. User is identified by token (same as in UserInfo case).

POST /session/active HTTP/1.1
Host: server.example.com
Content-Type: application/x-www-form-urlencoded
Authorization: Bearer <access_token>

By default we will return json array without session ids:

[
    {
        "exp": 1419356238,
         "iat": 1419350238,
         "lastUsedAt": 1419350238         
    },
    {
        "exp": 1419356247,
         "iat": 1419350247,
         "lastUsedAt": 1419350247
    }
]

We need Interception Script which should allow to modify response (and include id) if really needed.

E.g.

[
    {
        "exp": 1419356238,
         "iat": 1419350238,
         "lastUsedAt": 1419350238,
         "id": "6d2dda0e-8883-4df8-9429-d4a3504309c6",
         "browser": "chrome"
    },
    {
        "exp": 1419356247,
         "iat": 1419350247,
         "lastUsedAt": 1419350247,
         "id": "332dda0e-8883-4df8-9429-d4a350430933",
         "browser": "firefox"
    }
]

Note: scope required for calling this token endpoint should be configurable by a property (something like activeSessionAuthorizationScope by default.

[yuriyz]

Endpoint can be turned on/off by active_session value.

"enabledComponents": [
    "active_session",
    "par",
   ...
]

Token must have scope which is defined by activeSessionAuthorizationScope configuration property.
openid scope is required too, similar to /userinfo endpoint.

[yuriyz]

Implemented.
Sample script can be found here.