Adds a validated set for unity build targets when starting editor

Author: derekfreed

UnitySetup/UnitySetup.psm1

@@ -620,6 +620,7 @@ function Start-UnityEditor
         [parameter(Mandatory=$false)]
         [string]$LogFile,
         [parameter(Mandatory=$false)]
+        [ValidateSet('StandaloneOSX','StandaloneWindows','iOS','Android','StandaloneLinux','StandaloneWindows64','WebGL','WSAPlayer','StandaloneLinux64','StandaloneLinuxUniversal','Tizen','PSP2','PS4','XBoxOne','N3DS','WiiU','tvOS','Switch')]
         [string]$BuildTarget,
         [parameter(Mandatory=$false)]
         [switch]$BatchMode,