Update code to handle cert validation properly

This code contains duplication from HD's PR. Once his has been landed
this code can be fixed up a bit so that duplication is removed.

lib/msf/core/handler/reverse_https.rb

@@ -43,7 +43,8 @@ module ReverseHttps
 
     register_advanced_options(
       [
-        OptPath.new('HandlerSSLCert', [false, "Path to a SSL certificate in unified PEM format"])
+        OptPath.new('HandlerSSLCert', [false, "Path to a SSL certificate in unified PEM format"]),
+        OptBool.new('StagerVerifySSLCert', [false, "Whether to verify the SSL certificate in Meterpreter"])
       ], Msf::Handler::ReverseHttps)
 
   end