Add a note about tap-go migration

Signed-off-by: Muyassarov, Feruzjon <[email protected]>

Author: fmuyassarov

util/tap/README.md

@@ -5,3 +5,6 @@ interface between tests and a test harness.  This package helps Go to generate
 TAP output.
 
 Read the [full package documentation](https://godoc.org/github.com/mndrix/tap-go)
+
+NOTE: This code was originally located at https://github.com/mndrix/tap-go and
+migrated to here as thre project was archieved.