Update supported versions of databases

Author: alex-kulakov

ReadMe.md

@@ -3,14 +3,16 @@
 DataObjects.Net is a persistence and object-relational mapping framework for the Microsoft .NET. It allows developers to define persistent objects as well as business logic directly in C#, Visual Basic or F#. The persistent objects can be retrieved by LINQ queries. Persistent data can be stored in SQL Servers. In contrast to many other ORM frameworks the database model is generated and maintained automatically.
 
 Supported databases:
-- MS SQL Server 2008 R2, 2012, 2014, 2016, 2017, 2019
+- MS SQL Server 2012, 2014, 2016, 2017, 2019
 - MS Azure SQL Database
 - Oracle 10g, 11g
-- PostgreSQL 8.3, 8.4, 9.0, 9.1, 9.2, 10, 11
-- MySQL 5.5, 5.6, 5.7, 8.0
-- Firebird 2.5
+- PostgreSQL 9.x, 10, 11, 12, 13
+- MySQL 5.6, 5.7, 8.0
+- Firebird 2.5, 4.0
 - Sqlite 3
 
+NOTE that MS SQL Server 2008 R2, PostgreSQL v8.3, v8.4, and MySQL v5.5 were removed from supported versions list because they're too old and reached End-Of-Live status. Drivers for these versions still exist within libraries and we will try to keep them working but no guarantee given.
+
 ### Installation
 
 DataObjects.Net is available on Nuget. Install main package (NOTE this package does not include any providers, install needed provider addtionally)