Remove Reddit (abandoned)

The open source version of reddit has been retired. From the README:

> This repository is archived and will not receive any updates or accept issues or pull requests.

Maintainers announcement: https://www.reddit.com/r/changelog/comments/6xfyfg/an_update_on_the_state_of_the_redditreddit_and/

From @evaryont:
>Before October 14th, Reddit hadn't committed anything to the repository since April of this year. Then at the beginning of the month they pushed a few commits that cleaned up the repository for it's archival status. Discounting those recent commits, there hasn't been any commits to the repository for 6 months.
>Given the fact that the repository has been officially archived and the 6 month threshold has been hit (sorta), the link should probably be removed. A community fork can be re-added at a later time through the normal process.

README.md

@@ -394,7 +394,6 @@ _[IPBX](https://en.wikipedia.org/wiki/IP_PBX) telephony software_
   * [phpBB](https://www.phpbb.com/) - Flat-forum bulletin board software solution that can be used to stay in touch with a group of people or can power your entire website. ([Source Code](https://github.com/phpbb/phpbb)) `GPLv2` `PHP`
   * [PPnet](https://github.com/pixelpark/ppnet) - Create and host your own social network. `MIT` `Javascript`
   * [Pump.io](http://pump.io/) - Stream server that does most of what people really want from a social network. ([Source Code](https://github.com/e14n/pump.io)) `Apache` `Nodejs`
-  * [Reddit](https://www.reddit.com/) - Social networking and news website where registered community members can submit content. ([Demo](https://www.reddit.com/), [Source Code](https://github.com/reddit/reddit)) `CPALv1` `Python`
   * [Socialhome](https://socialhome.network) - Federated and decentralized profile builder and social network engine. ([Demo](https://socialhome.network/public/), [Source Code](https://github.com/jaywink/socialhome)) `AGPLv3` `Python`
   * [Symphony](https://hacpai.com/) - A modern community (forum/SNS/blog) platform written in Java. ([Source Code](https://github.com/b3log/symphony)) `GPLv3` `Java`
   * [Telescope](http://www.telescopeapp.org/) - An open-source social news app built with Meteor. ([Demo](http://demo.telescopeapp.org/), [Source Code](https://github.com/TelescopeJS/Telescope)) `MIT` `Nodejs`