Add mention of int8 support

Author: jeromew

README.md

@@ -282,7 +282,7 @@ For all supported types, their corresponding array version is also supported.
 
 - bool
 - bytea
-- int2, int4
+- int2, int4, int8
 - float4, float8
 - text
 - varchar
@@ -296,6 +296,10 @@ The types for array (one or more dimentions) corresponds to the type prefixed wi
 
 ## changelog
 
+### version 2.2.0 - published 2021-09-13
+
+- Add int8 type support (usage requires node version 10.20+)
+
 ### version 2.1.0 - published 2021-08-25
 
 - Add varchar type support