Wt

The following forum post got me to look at Wt::Mail::Client: https://redmine.emweb.be/boards/2/topics/18269

I observed the following:

• If the resolver fails, Client::connect throws an exception instead of returning false (as documented)
• If the client is not connected, and Client::send is used, this will result in a null pointer dereference, this can be due to:
  • the user forgetting to call connect
  • similarly, send being called after disconnect
  • connect being used with TransportEncryption set to anything other than None, but Wt is built without OpenSSL (Wt will log "TLS requested, but Wt built without OpenSSL").

I think we should fix the client so:

• Client::connect logs an error and returns false if the resolver fails (matching the documentation)
• Client::send logs an error and returns false if the client is not connected