Merge pull request nginx-proxy#767 from thomasleveil/patch-1

DOC: reflect change from PR nginx-proxy#344

Author: jwilder

README.md

@@ -203,7 +203,7 @@ is always preferred when available.
 Note that in the latter case, a browser may get an connection error as no certificate is available
 to establish a connection.  A self-signed or generic cert named `default.crt` and `default.key`
 will allow a client browser to make a SSL connection (likely w/ a warning) and subsequently receive
-a 503.
+a 500.
 
 To serve traffic in both SSL and non-SSL modes without redirecting to SSL, you can include the
 environment variable `HTTPS_METHOD=noredirect` (the default is `HTTPS_METHOD=redirect`).  You can also