drop zone, and remove beta tag from mraid checker

run-standalone.ps1

@@ -0,0 +1,11 @@
+$ErrorActionPreference = 'Stop'
+
+$root = Split-Path -Parent $MyInvocation.MyCommand.Path
+$standalone = Join-Path $root 'standalone'
+
+Push-Location $standalone
+try {
+  go run .
+} finally {
+  Pop-Location
+}