Add RSS Guard to list of software (#3627)

README.md

@@ -112,6 +112,7 @@ and [Fever API](https://freshrss.github.io/FreshRSS/en/users/06_Fever_API.html)
 |:--------------------------------------------------------------------------------------|:-----------:|:-------------------------------------------------------------:|:----------------------:|:----------------:|:-------------:|:---------:|:------------------------------:|:-------------------:|:----------:|:------:|:--------:|:------------:|
 | [News+](https://play.google.com/store/apps/details?id=com.noinnion.android.newsplus) with [Google Reader extension](https://github.com/noinnion/newsplus/blob/master/apk/GoogleReaderCloneExtension_101.apk) | Android | [Partially](https://github.com/noinnion/newsplus/blob/master/extensions/GoogleReaderCloneExtension/src/com/noinnion/android/newsplus/extension/google_reader/) | 2015       | GReader | ✔️             | ⭐⭐⭐       | ✔️                    | ✔️                 | ✔️         | ✔️     | ✔️       | ✔️           |
 | [FeedMe](https://play.google.com/store/apps/details?id=com.seazon.feedme)             | Android     | ➖                                                            | ✔️✔️                   | GReader          | ✔️            | ⭐⭐        | ➖                             | ➖                  | ✔️         | ✓     | ✔️       | ✔️           |
+| [RSS Guard](https://github.com/martinrotter/rssguard) | Windows, GNU/Linux, MacOS, OS/2 | ✔️ | ✔️✔️ | GReader | ✔️ | ⭐ | ➖ | ✔️ | ✔️ | ✔️ | ✔️ | ➖ |
 | [EasyRSS](https://github.com/Alkarex/EasyRSS)                                         | Android     | [✔️](https://github.com/Alkarex/EasyRSS)                      | ✔️                     | GReader          | Bug           | ⭐⭐        | ➖                             | ➖                  | ✔️         | ➖     | ➖       | ➖           |
 | [Readrops](https://github.com/readrops/Readrops)                                      | Android     | [✔️](https://github.com/readrops/Readrops)                    | ✔️✔️                   | GReader          | ✔️            | ⭐⭐⭐       | ➖                             | ➖                  | ➖         | ➖     | ➖       | ✔️           |
 | [FocusReader](https://play.google.com/store/apps/details?id=allen.town.focus.reader)  | Android     | ➖                                                            | ✔️✔️                   | GReader          | ✔️            | ⭐⭐⭐       | ➖                             | ➖                  | ✔️         | ➖     | ✓       | ✔️           |