Merge pull request #35 from anwarchk/master

Update step for installing mesheryctl

Author: leecalcote

prereq/README.md

@@ -65,7 +65,8 @@ In this workshop, Meshery will run "off-cluster", which is to say it will be run
 #### Install on MacOS with Homebrew
 
 ```
-brew install layer5io/mesheryctl
+brew tap layer5io/tap
+brew install mesheryctl
 mesheryctl system start
 ```