Returns up to 100 recent public needs created by the given user, ordered by descending date of creation.
http://api.needish.com/needs/user/{user_id}.format
| user_id | Required. The id or nickname of the requested user. |
| limit | Optional (20). Limits the number of recent needs to retrieve. |
| page | Optional (1). The recent needs page to retrieve. |
| since | Optional. Returns needs created after the specified date. |
