Fix outdated website readme

The text on https://shopify.github.io/sarama/ is outdated. 

This updates the text to match the project readme.

Fix https://github.com/Shopify/sarama/issues/1248.

index.md

@@ -8,11 +8,9 @@ API documentation and examples are available via [godoc](https://godoc.org/githu
 
 ## Compatibility and API stability
 
-Sarama provides a "2 releases + 2 months" compatibility guarantee: we support
+Sarama provides a "2 releases + 2 months" compatibility guarantee: we support the two latest stable releases of
-the two latest stable releases of Kafka and Go, and we provide a two month
+Kafka and Go, and we provide a two month grace period for older releases. This means we currently officially
-grace period for older releases. This means we currently officially support
+support Go 1.12 through 1.14, and Kafka 2.1 through 2.4, although older releases are still likely to work.
-Go 1.7 and 1.6, and Kafka 0.10.0 and 0.9.0, although older releases are still
-likely to work.
 
 Sarama follows semantic versioning and provides API stability via the gopkg.in service.
 You can import a version with a guaranteed stable API via http://gopkg.in/Shopify/sarama.v1.