Add a small note to bypassuac_injection concerning EXE::Custom

Author: Meatballs1

modules/exploits/windows/local/bypassuac_injection.rb

@@ -24,6 +24,8 @@ def initialize(info={})
         technique to drop only the DLL payload binary instead of three seperate
         binaries in the standard technique. However, it requires the correct
         architecture to be selected, (use x64 for SYSWOW64 systems also).
+        If specifying EXE::Custom your DLL should call ExitProcess() after starting
+        your payload in a seperate process.
       },
       'License'       => MSF_LICENSE,
       'Author'        => [