Add librengine to Search Engines (#2910)

README.md

@@ -1564,6 +1564,7 @@ _Related: [Booking and Scheduling](#booking-and-scheduling)_
 
 - [Ambar](https://ambar.cloud) - Document Search Engine (OCR, Store & Search). ([Demo](https://app.ambar.cloud/), [Source Code](https://github.com/RD17/ambar)) `MIT` `Nodejs/Python`
 - [Gigablast](https://www.gigablast.com/) - open source search engine. ([Source Code](https://github.com/gigablast/open-source-search-engine)) `Apache-2.0` `C++`
+- [librengine](https://github.com/liameno/librengine) - Private web search engine. `GPL-3.0` `C++`
 - [Jina](https://github.com/jina-ai/jina/) - Cloud-native neural search framework for any kind of data. `Apache-2.0` `Python`
 - [MeiliSearch](https://meilisearch.com) - Ultra relevant, instant and typo-tolerant full-text search API. ([Source Code](https://github.com/meilisearch/MeiliSearch)) `MIT` `Rust`
 - [Searx](https://searx.github.io/searx/) - Privacy-respecting, hackable metasearch engine. ([Demo](https://searx.me/), [Source Code](https://github.com/searx/searx)) `AGPL-3.0` `Python`