Add Vert.x support to the README

Author: pimterry

README.md

@@ -22,6 +22,7 @@ Traffic can be captured from at least:
 - [x] Spring WebClient
 - [x] Ktor-Client
 - [x] Akka-HTTP v10.1.6+
+- [x] Vert.x HttpClient and WebClient
 
 This will also capture HTTP(S) from any downstream libraries based on each of these clients, and many other untested clients sharing similar implementations, and so should cover a very large percentage of HTTP client usage.