2.3) Add setting for using SSL connections in login when $cfg['AllowArbitraryServer']=true

When $cfg['AllowArbitraryServer'] is true, the user can enter the server to connect to, but doesn't have option to enable ssl connection.

[I suggest to try ssl connection first and use it by default for non local machine 127.0.0.1/localhost, if it failed try non-ssl connection and show message about it [as in point 2.2 #12354]]

Motivations:

• Increase usage of MYSQL TLS connections (avoid sniffing/MITM attacks)