Repository: praw-dev/praw

Issue:
mark_visited function appears to be broken or using the wrong endpoint
## Issue Description
I was tooling around in an interactive session so I don't have a super clean source code snippet, but I tried to mark a submission as visited and got this error instead. 
```
In [44]: submi = reddit.submission(s.id) 

In [45]: submi.mark_visited() 
---------------------------------------------------------------------------
Forbidden                                 Traceback (most recent call last)
~/reddit_opioid_mining/scraper.py in <module>()
----> 1 submi.mark_visited()

/usr/local/lib/python3.5/dist-packages/praw/models/reddit/submission.py in mark_visited(self)
    181         """
    182         data = {'links': self.fullname}
--> 183         self._reddit.post(API_PATH['store_visits'], data=data)
    184 
    185     def hide(self, other_submissions=None):

/usr/local/lib/python3.5/dist-packages/praw/reddit.py in post(self, path, data, files, params)
    463         """
    464         data = self.request('POST', path, data=data or {}, files=files,
--> 465                             params=params)
    466         return self._objector.objectify(data)
    467 

/usr/local/lib/python3.5/dist-packages/praw/reddit.py in request(self, method, path, params, data, files)
    504         """
    505         return self._core.request(method, path, data=data, files=files,
--> 506                                   params=params)
    507 
    508     def submission(  # pylint: disable=invalid-name,redefined-builtin

/usr/local/lib/python3.5/dist-packages/prawcore/sessions.py in request(self, method, path, data, files, json, params)
    183         return self._request_with_retries(
    184             data=data, files=files, json=json, method=method,
--> 185             params=params, url=url)
    186 
    187 

/usr/local/lib/python3.5/dist-packages/prawcore/sessions.py in _request_with_retries(self, data, files, json, method, params, url, retries)
    128                                   retries, saved_exception, url)
    129         elif response.status_code in self.STATUS_EXCEPTIONS:
--> 130             raise self.STATUS_EXCEPTIONS[response.status_code](response)
    131         elif response.status_code == codes['no_content']:
    132             return

Forbidden: received 403 HTTP response
```


## System Information

- PRAW Version: 6.0.0
- Python Version: 3.5.2
- Operating System: Ubuntu 16.04



Discussion:
`Submission.mark_visited()` hits [`/api/store_visits`](https://www.reddit.com/dev/api/#POST_api_store_visits) and the endpoint requires [Reddit Premium](https://www.reddit.com/premium) (formerly known as Reddit Gold). 
Oh okay, thats it. Thanks.

On Tue, Nov 20, 2018, 8:27 AM nmtake <notifications@github.com> wrote:

> Submission.mark_visited() hits /api/store_visits
> <https://www.reddit.com/dev/api/#POST_api_store_visits> and the endpoint
> requires Reddit Premium <https://www.reddit.com/premium> (formerly known
> as Reddit Gold).
>
> —
> You are receiving this because you authored the thread.
> Reply to this email directly, view it on GitHub
> <https://github.com/praw-dev/praw/issues/981#issuecomment-440272872>, or mute
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> <https://github.com/notifications/unsubscribe-auth/AFiX7WkclgrHWnyNgcWT_OXkGNpYrK3Eks5uxAMzgaJpZM4Yp5dK>
> .
>


Resolving patch:
diff --git a/praw/models/reddit/submission.py b/praw/models/reddit/submission.py
--- a/praw/models/reddit/submission.py
+++ b/praw/models/reddit/submission.py
@@ -216,6 +216,8 @@ def _info_path(self):
     def mark_visited(self):
         """Mark submission as visited.
 
+        This method requires a subscription to reddit premium.
+
         Example usage:
 
         .. code:: python


Test patch: