Update PROJECTS.md

Author: alexeyr

PROJECTS.md

@@ -55,3 +55,4 @@ _Please support the project by [emailing Justin Gordon](mailto:justin@shakacode.
 - [github.com/tswayne/react-helper](https://github.com/tswayne/react-helper)
 - [github.com/KissKissBankBank/kitten](https://github.com/KissKissBankBank/kitten)
 - [github.com/sharetribe/sharetribe](https://github.com/sharetribe/sharetribe): Open source marketplace platform.
+- [GitHub search for repos using `react_on_rails`](https://github.com/search?q=gem+react_on_rails&ref=advsearch&type=repositories&utf8=%E2%9C%93) (may include some false positives)