Add Redis3m to Database section

Author: luca3m

README.md

@@ -208,6 +208,7 @@ A curated list of awesome C/C++ frameworks, libraries, resources, and shiny thin
 
 * [hiberlite](https://github.com/paulftw/hiberlite) - C++ Object-relational mapping for sqlite3. [BSD]
 * [Hiredis](https://github.com/redis/hiredis) - A minimalistic C client library for the Redis database. [BSD]
+* [redis3m](https://github.com/luca3m/redis3m) - Wrapper of hiredis with clean C++ interface, supporting sentinel and ready to use patterns [Apache2]
 * [LevelDB](https://github.com/google/leveldb) - A fast key-value storage library. [BSD]
 * [LMDB](http://symas.com/mdb/) - Very fast embedded key/value store with full ACID semantics. [OpenLDAP]
 * [MongoDB C Driver](https://github.com/mongodb/mongo-c-driver) - MongoDB client library for C. [Apache2]