Allow save pre-config list of servers (Website)

[alexzvn]

To save pre-config, just simply create servers.json same level with index.html

Example config

[
    { "serverName": "Server without SSL", "serverURI": "ws://localhost:8080" },
    { "serverName": "Server with SSL", "serverURI": "wss://localhost:3000" }
]

[mesacarlos]

Thank you for your contribution!