Mention PostgreSQL

It seems worth mentioning explicitly if Dapper works with PostgreSQL or not. I assume it does based on the remark that "it works across all .net ado providers", but am not sure because it's not mentioned explicitly...

Readme.md

@@ -342,7 +342,7 @@ Dapper does not manage your connection's lifecycle, it assumes the connection it
 
 Will dapper work with my db provider?
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-Dapper has no DB specific implementation details, it works across all .net ado providers including sqlite, sqlce, firebird, oracle, MySQL and SQL Server
+Dapper has no DB specific implementation details, it works across all .net ado providers including sqlite, sqlce, firebird, oracle, MySQL, PostgreSQL and SQL Server
 
 Do you have a comprehensive list of examples?
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