Add LibraDB and Chronos (#4462)

README.md

@@ -678,6 +678,7 @@ _Data stores with expiring records, in-memory distributed data stores, or in-mem
 - [influxdb](https://github.com/influxdb/influxdb) - Scalable datastore for metrics, events, and real-time analytics.
 - [ledisdb](https://github.com/siddontang/ledisdb) - Ledisdb is a high performance NoSQL like Redis based on LevelDB.
 - [levigo](https://github.com/jmhodges/levigo) - Levigo is a Go wrapper for LevelDB.
+- [libradb](https://github.com/amit-davidson/LibraDB) - LibraDB is a simple database with less then 1000 lines of code for learning. 
 - [lotusdb](https://github.com/flower-corp/lotusdb) - Fast k/v database compatible with lsm and b+tree.
 - [Milvus](https://github.com/milvus-io/milvus) - Milvus is a vector database for embedding management, analytics and search.
 - [moss](https://github.com/couchbase/moss) - Moss is a simple LSM key-value storage engine written in 100% Go.
@@ -2954,6 +2955,7 @@ _Source code analysis tools, also known as Static Application Security Testing (
 - [asty](https://github.com/asty-org/asty) - Converts golang AST to JSON and JSON to AST.
 - [blanket](https://gitlab.com/verygoodsoftwarenotvirus/blanket) - blanket is a tool that helps you catch functions which don't have direct unit tests in your Go packages.
 - [ChainJacking](https://github.com/Checkmarx/chainjacking) - Find which of your Go lang direct GitHub dependencies is susceptible to ChainJacking attack.
+- [Chronos](https://github.com/amit-davidson/Chronos) - Detects race conditions statically
 - [dupl](https://github.com/mibk/dupl) - Tool for code clone detection.
 - [errcheck](https://github.com/kisielk/errcheck) - Errcheck is a program for checking for unchecked errors in Go programs.
 - [gcvis](https://github.com/davecheney/gcvis) - Visualise Go program GC trace data in real time.
@@ -3462,6 +3464,7 @@ _Add the group of your city/country here (send **PR**)_
 - [50 Shades of Go](https://devs.cloudimmunity.com/gotchas-and-common-mistakes-in-go-golang/) - Traps, Gotchas, and Common Mistakes for New Golang Devs.
 - [A Guide to Golang E-Commerce](https://snipcart.com/blog/golang-ecommerce-ponzu-cms-demo?utm_term=golang-ecommerce-ponzu-cms-demo) - Building a Golang site for e-commerce (demo included).
 - [A Tour of Go](https://tour.golang.org/) - Interactive tour of Go.
+- [Build a Database in 1000 lines of code]( https://link.medium.com/O9YQlx89Htb) - Build a NoSQL Database From Zero in 1000 Lines of Code. 
 - [Build web application with Golang](https://github.com/astaxie/build-web-application-with-golang) - Golang ebook intro how to build a web app with golang.
 - [Building and Testing a REST API in Go with Gorilla Mux and PostgreSQL](https://semaphoreci.com/community/tutorials/building-and-testing-a-rest-api-in-go-with-gorilla-mux-and-postgresql) - We’ll write an API with the help of the powerful Gorilla Mux.
 - [Building Go Web Applications and Microservices Using Gin](https://semaphoreci.com/community/tutorials/building-go-web-applications-and-microservices-using-gin) - Get familiar with Gin and find out how it can help you reduce boilerplate code and build a request handling pipeline.