highlight experimental branch features

Author: Matt Howlett

README.md

@@ -55,7 +55,7 @@ dotnet add package -v 0.11.4 Confluent.Kafka
 
 We have started working towards a 1.0 release of the library which will occur after we add idempotence and transaction features. In order to best accomodate these and other changes,
 we will be making breaking changes to the API in that release. You can track our progress on the `1.0-experimental` branch (as well as corresponding packages on
-[nuget.org](https://www.nuget.org/packages/Confluent.Kafka/)). We have already added an *AdminClient* as well as support for *message headers* and *custom timestamps* amongst other things.
+[nuget.org](https://www.nuget.org/packages/Confluent.Kafka/)). We have already added an **AdminClient** as well as support for **message headers** and **custom timestamps** amongst other things.
 Note that all work on this branch is subject to change and should not be considered production ready. All feedback is very welcome!
 
 Also, nuget packages corresponding to all release branch commits are available from the following nuget package source (Note: this is not a web url - you should specify it in the nuget package manger):